diff --git a/networks/kovan-fork.json b/networks/kovan-fork.json
new file mode 100644
index 000000000..9ba4a23e7
--- /dev/null
+++ b/networks/kovan-fork.json
@@ -0,0 +1,4 @@
+{
+  "url": "https://kovan.infura.io/v3/e1a5d4d2c06a4e81945fca56d0d5d8ea",
+  "unlocked": ["0xA776184Fd6F545DAe5f51361dBcC9018549a9749"]
+}
diff --git a/networks/mainnet-abi.json b/networks/mainnet-abi.json
index df2fad107..612af7a15 100644
--- a/networks/mainnet-abi.json
+++ b/networks/mainnet-abi.json
@@ -3974,6 +3974,614 @@
             "signature": "0xdd62ed3e"
         }
     ],
+    "SAI": [
+      {
+        "constant": true,
+        "inputs": [
+          
+        ],
+        "name": "name",
+        "outputs": [
+          {
+            "name": "",
+            "type": "bytes32"
+          }
+        ],
+        "payable": false,
+        "stateMutability": "view",
+        "type": "function"
+      },
+      {
+        "constant": false,
+        "inputs": [
+          
+        ],
+        "name": "stop",
+        "outputs": [
+          
+        ],
+        "payable": false,
+        "stateMutability": "nonpayable",
+        "type": "function"
+      },
+      {
+        "constant": false,
+        "inputs": [
+          {
+            "name": "guy",
+            "type": "address"
+          },
+          {
+            "name": "wad",
+            "type": "uint256"
+          }
+        ],
+        "name": "approve",
+        "outputs": [
+          {
+            "name": "",
+            "type": "bool"
+          }
+        ],
+        "payable": false,
+        "stateMutability": "nonpayable",
+        "type": "function"
+      },
+      {
+        "constant": false,
+        "inputs": [
+          {
+            "name": "owner_",
+            "type": "address"
+          }
+        ],
+        "name": "setOwner",
+        "outputs": [
+          
+        ],
+        "payable": false,
+        "stateMutability": "nonpayable",
+        "type": "function"
+      },
+      {
+        "constant": true,
+        "inputs": [
+          
+        ],
+        "name": "totalSupply",
+        "outputs": [
+          {
+            "name": "",
+            "type": "uint256"
+          }
+        ],
+        "payable": false,
+        "stateMutability": "view",
+        "type": "function"
+      },
+      {
+        "constant": false,
+        "inputs": [
+          {
+            "name": "src",
+            "type": "address"
+          },
+          {
+            "name": "dst",
+            "type": "address"
+          },
+          {
+            "name": "wad",
+            "type": "uint256"
+          }
+        ],
+        "name": "transferFrom",
+        "outputs": [
+          {
+            "name": "",
+            "type": "bool"
+          }
+        ],
+        "payable": false,
+        "stateMutability": "nonpayable",
+        "type": "function"
+      },
+      {
+        "constant": true,
+        "inputs": [
+          
+        ],
+        "name": "decimals",
+        "outputs": [
+          {
+            "name": "",
+            "type": "uint256"
+          }
+        ],
+        "payable": false,
+        "stateMutability": "view",
+        "type": "function"
+      },
+      {
+        "constant": false,
+        "inputs": [
+          {
+            "name": "guy",
+            "type": "address"
+          },
+          {
+            "name": "wad",
+            "type": "uint256"
+          }
+        ],
+        "name": "mint",
+        "outputs": [
+          
+        ],
+        "payable": false,
+        "stateMutability": "nonpayable",
+        "type": "function"
+      },
+      {
+        "constant": false,
+        "inputs": [
+          {
+            "name": "wad",
+            "type": "uint256"
+          }
+        ],
+        "name": "burn",
+        "outputs": [
+          
+        ],
+        "payable": false,
+        "stateMutability": "nonpayable",
+        "type": "function"
+      },
+      {
+        "constant": false,
+        "inputs": [
+          {
+            "name": "name_",
+            "type": "bytes32"
+          }
+        ],
+        "name": "setName",
+        "outputs": [
+          
+        ],
+        "payable": false,
+        "stateMutability": "nonpayable",
+        "type": "function"
+      },
+      {
+        "constant": true,
+        "inputs": [
+          {
+            "name": "src",
+            "type": "address"
+          }
+        ],
+        "name": "balanceOf",
+        "outputs": [
+          {
+            "name": "",
+            "type": "uint256"
+          }
+        ],
+        "payable": false,
+        "stateMutability": "view",
+        "type": "function"
+      },
+      {
+        "constant": true,
+        "inputs": [
+          
+        ],
+        "name": "stopped",
+        "outputs": [
+          {
+            "name": "",
+            "type": "bool"
+          }
+        ],
+        "payable": false,
+        "stateMutability": "view",
+        "type": "function"
+      },
+      {
+        "constant": false,
+        "inputs": [
+          {
+            "name": "authority_",
+            "type": "address"
+          }
+        ],
+        "name": "setAuthority",
+        "outputs": [
+          
+        ],
+        "payable": false,
+        "stateMutability": "nonpayable",
+        "type": "function"
+      },
+      {
+        "constant": true,
+        "inputs": [
+          
+        ],
+        "name": "owner",
+        "outputs": [
+          {
+            "name": "",
+            "type": "address"
+          }
+        ],
+        "payable": false,
+        "stateMutability": "view",
+        "type": "function"
+      },
+      {
+        "constant": true,
+        "inputs": [
+          
+        ],
+        "name": "symbol",
+        "outputs": [
+          {
+            "name": "",
+            "type": "bytes32"
+          }
+        ],
+        "payable": false,
+        "stateMutability": "view",
+        "type": "function"
+      },
+      {
+        "constant": false,
+        "inputs": [
+          {
+            "name": "guy",
+            "type": "address"
+          },
+          {
+            "name": "wad",
+            "type": "uint256"
+          }
+        ],
+        "name": "burn",
+        "outputs": [
+          
+        ],
+        "payable": false,
+        "stateMutability": "nonpayable",
+        "type": "function"
+      },
+      {
+        "constant": false,
+        "inputs": [
+          {
+            "name": "wad",
+            "type": "uint256"
+          }
+        ],
+        "name": "mint",
+        "outputs": [
+          
+        ],
+        "payable": false,
+        "stateMutability": "nonpayable",
+        "type": "function"
+      },
+      {
+        "constant": false,
+        "inputs": [
+          {
+            "name": "dst",
+            "type": "address"
+          },
+          {
+            "name": "wad",
+            "type": "uint256"
+          }
+        ],
+        "name": "transfer",
+        "outputs": [
+          {
+            "name": "",
+            "type": "bool"
+          }
+        ],
+        "payable": false,
+        "stateMutability": "nonpayable",
+        "type": "function"
+      },
+      {
+        "constant": false,
+        "inputs": [
+          {
+            "name": "dst",
+            "type": "address"
+          },
+          {
+            "name": "wad",
+            "type": "uint256"
+          }
+        ],
+        "name": "push",
+        "outputs": [
+          
+        ],
+        "payable": false,
+        "stateMutability": "nonpayable",
+        "type": "function"
+      },
+      {
+        "constant": false,
+        "inputs": [
+          {
+            "name": "src",
+            "type": "address"
+          },
+          {
+            "name": "dst",
+            "type": "address"
+          },
+          {
+            "name": "wad",
+            "type": "uint256"
+          }
+        ],
+        "name": "move",
+        "outputs": [
+          
+        ],
+        "payable": false,
+        "stateMutability": "nonpayable",
+        "type": "function"
+      },
+      {
+        "constant": false,
+        "inputs": [
+          
+        ],
+        "name": "start",
+        "outputs": [
+          
+        ],
+        "payable": false,
+        "stateMutability": "nonpayable",
+        "type": "function"
+      },
+      {
+        "constant": true,
+        "inputs": [
+          
+        ],
+        "name": "authority",
+        "outputs": [
+          {
+            "name": "",
+            "type": "address"
+          }
+        ],
+        "payable": false,
+        "stateMutability": "view",
+        "type": "function"
+      },
+      {
+        "constant": false,
+        "inputs": [
+          {
+            "name": "guy",
+            "type": "address"
+          }
+        ],
+        "name": "approve",
+        "outputs": [
+          {
+            "name": "",
+            "type": "bool"
+          }
+        ],
+        "payable": false,
+        "stateMutability": "nonpayable",
+        "type": "function"
+      },
+      {
+        "constant": true,
+        "inputs": [
+          {
+            "name": "src",
+            "type": "address"
+          },
+          {
+            "name": "guy",
+            "type": "address"
+          }
+        ],
+        "name": "allowance",
+        "outputs": [
+          {
+            "name": "",
+            "type": "uint256"
+          }
+        ],
+        "payable": false,
+        "stateMutability": "view",
+        "type": "function"
+      },
+      {
+        "constant": false,
+        "inputs": [
+          {
+            "name": "src",
+            "type": "address"
+          },
+          {
+            "name": "wad",
+            "type": "uint256"
+          }
+        ],
+        "name": "pull",
+        "outputs": [
+          
+        ],
+        "payable": false,
+        "stateMutability": "nonpayable",
+        "type": "function"
+      },
+      {
+        "inputs": [
+          {
+            "name": "symbol_",
+            "type": "bytes32"
+          }
+        ],
+        "payable": false,
+        "stateMutability": "nonpayable",
+        "type": "constructor"
+      },
+      {
+        "anonymous": false,
+        "inputs": [
+          {
+            "indexed": true,
+            "name": "guy",
+            "type": "address"
+          },
+          {
+            "indexed": false,
+            "name": "wad",
+            "type": "uint256"
+          }
+        ],
+        "name": "Mint",
+        "type": "event"
+      },
+      {
+        "anonymous": false,
+        "inputs": [
+          {
+            "indexed": true,
+            "name": "guy",
+            "type": "address"
+          },
+          {
+            "indexed": false,
+            "name": "wad",
+            "type": "uint256"
+          }
+        ],
+        "name": "Burn",
+        "type": "event"
+      },
+      {
+        "anonymous": false,
+        "inputs": [
+          {
+            "indexed": true,
+            "name": "authority",
+            "type": "address"
+          }
+        ],
+        "name": "LogSetAuthority",
+        "type": "event"
+      },
+      {
+        "anonymous": false,
+        "inputs": [
+          {
+            "indexed": true,
+            "name": "owner",
+            "type": "address"
+          }
+        ],
+        "name": "LogSetOwner",
+        "type": "event"
+      },
+      {
+        "anonymous": true,
+        "inputs": [
+          {
+            "indexed": true,
+            "name": "sig",
+            "type": "bytes4"
+          },
+          {
+            "indexed": true,
+            "name": "guy",
+            "type": "address"
+          },
+          {
+            "indexed": true,
+            "name": "foo",
+            "type": "bytes32"
+          },
+          {
+            "indexed": true,
+            "name": "bar",
+            "type": "bytes32"
+          },
+          {
+            "indexed": false,
+            "name": "wad",
+            "type": "uint256"
+          },
+          {
+            "indexed": false,
+            "name": "fax",
+            "type": "bytes"
+          }
+        ],
+        "name": "LogNote",
+        "type": "event"
+      },
+      {
+        "anonymous": false,
+        "inputs": [
+          {
+            "indexed": true,
+            "name": "src",
+            "type": "address"
+          },
+          {
+            "indexed": true,
+            "name": "guy",
+            "type": "address"
+          },
+          {
+            "indexed": false,
+            "name": "wad",
+            "type": "uint256"
+          }
+        ],
+        "name": "Approval",
+        "type": "event"
+      },
+      {
+        "anonymous": false,
+        "inputs": [
+          {
+            "indexed": true,
+            "name": "src",
+            "type": "address"
+          },
+          {
+            "indexed": true,
+            "name": "dst",
+            "type": "address"
+          },
+          {
+            "indexed": false,
+            "name": "wad",
+            "type": "uint256"
+          }
+        ],
+        "name": "Transfer",
+        "type": "event"
+      }
+    ],
     "StdComptroller": [
         {
             "constant": true,
diff --git a/package.json b/package.json
index 622193cbb..6a92408da 100644
--- a/package.json
+++ b/package.json
@@ -18,7 +18,8 @@
   "license": "UNLICENSED",
   "devDependencies": {
     "bignumber.js": "8.0.1",
-    "ganache-core": "^2.9.0-istanbul.0",
+    "ganache-cli": "^6.7.0",
+    "ganache-core": "^2.8.0",
     "immutable": "^4.0.0-rc.12",
     "jest": "^24.9.0",
     "jest-cli": "^24.9.0",
@@ -28,7 +29,7 @@
     "solparse": "^2.2.8"
   },
   "dependencies": {
-    "eth-saddle": "^0.0.25",
+    "eth-saddle": "^0.0.30",
     "truffle-hdwallet-provider": "^1.0.17",
     "web3": "^1.2.4"
   },
diff --git a/scenario/package.json b/scenario/package.json
index bb96477c3..28382e643 100644
--- a/scenario/package.json
+++ b/scenario/package.json
@@ -4,7 +4,8 @@
   "description": "The Compound Money Market",
   "main": "index.js",
   "scripts": {
-    "build": "./script/webpack"
+    "build": "./script/webpack",
+    "postinstall": "rm node_modules/ganache-core/typings/index.d.ts"
   },
   "repository": "git@github.com:compound-finance/money-market.git",
   "author": "Compound Finance",
@@ -21,15 +22,12 @@
   },
   "dependencies": {
     "bignumber.js": "8.0.1",
-    "eth-saddle": "^0.0.25",
+    "eth-saddle": "^0.0.30",
     "ethers": "^4.0.0-beta.1",
     "ganache-core": "https://github.com/trufflesuite/ganache-core.git",
     "immutable": "^4.0.0-rc.12",
     "truffle-flattener": "^1.3.0",
     "truffle-hdwallet-provider": "1.0.5",
     "web3": "^1.2.4"
-  },
-  "resolutions": {
-    "scrypt.js": "https://registry.npmjs.org/@compound-finance/ethereumjs-wallet/-/ethereumjs-wallet-0.6.3.tgz"
   }
 }
diff --git a/scenario/script/repl b/scenario/script/repl
index 672f40042..2ec33eddd 100755
--- a/scenario/script/repl
+++ b/scenario/script/repl
@@ -21,6 +21,9 @@ while getopts ":hdn:e:s:vt" arg; do
 		d) # Dry run
 			dry_run="true"
 			;;
+		h) # Hypothetical
+			hypothetical="true"
+			;;
 		e) # Add variables for script (key=value,key2=value2)
 			env_vars="$OPTARG"
 			;;
@@ -28,10 +31,10 @@ while getopts ":hdn:e:s:vt" arg; do
 			network=$OPTARG
 			;;
 		s) # Specify a script to run
-			script=$OPTARG
-			[ ! -f "$script" ] \
-				&& echo "Cannot find script $script" \
+			[ ! -f "$OPTARG" ] \
+				&& echo "Cannot find script $OPTARG" \
 				&& exit 1
+			script+=("$OPTARG")
 			;;
 		t) # Don't build TSC
 			no_tsc="true"
diff --git a/scenario/src/Builder/InterestRateModelBuilder.ts b/scenario/src/Builder/InterestRateModelBuilder.ts
index c6db8cdcc..94822d5b1 100644
--- a/scenario/src/Builder/InterestRateModelBuilder.ts
+++ b/scenario/src/Builder/InterestRateModelBuilder.ts
@@ -3,12 +3,14 @@ import {addAction, World} from '../World';
 import {InterestRateModel} from '../Contract/InterestRateModel';
 import {Invokation, invoke} from '../Invokation';
 import {
+  getAddressV,
   getExpNumberV,
   getNumberV,
   getPercentV,
   getStringV,
 } from '../CoreValue';
 import {
+  AddressV,
   EventV,
   NumberV,
   StringV,
@@ -20,6 +22,7 @@ import {getContract, getTestContract} from '../Contract';
 const FixedInterestRateModel = getTestContract('InterestRateModelHarness');
 const WhitePaperInterestRateModel = getContract('WhitePaperInterestRateModel');
 const JumpRateModel = getContract('JumpRateModel');
+const DAIInterestRateModel = getContract('DAIInterestRateModel');
 
 export interface InterestRateModelData {
   invokation: Invokation<InterestRateModel>
@@ -47,7 +50,7 @@ export async function buildInterestRateModel(world: World, from: string, event:
         new Arg("rate", getPercentV),
       ],
       async (world, {name, rate}) => ({
-        invokation: await FixedInterestRateModel.deploy<InterestRateModel>(world, from, [rate.val]),
+        invokation: await FixedInterestRateModel.deploy<InterestRateModel>(world, from, [rate.encode()]),
         name: name.val,
         contract: "InterestRateModelHarness",
         description: `Fixed rate ${rate.show()} per block`
@@ -67,39 +70,66 @@ export async function buildInterestRateModel(world: World, from: string, event:
         new Arg("multiplier", getExpNumberV)
       ],
       async (world, {name, baseRate, multiplier}) => ({
-        invokation: await WhitePaperInterestRateModel.deploy<InterestRateModel>(world, from, [baseRate.val, multiplier.val]),
+        invokation: await WhitePaperInterestRateModel.deploy<InterestRateModel>(world, from, [baseRate.encode(), multiplier.encode()]),
         name: name.val,
         contract: "WhitePaperInterestRateModel",
-        description: `WhitePaper baseRate=${baseRate.val} multiplier=${multiplier.val}`,
+        description: `WhitePaper baseRate=${baseRate.encode().toString()} multiplier=${multiplier.encode().toString()}`,
         base: baseRate.encode().toString(),
         slope: multiplier.encode().toString()
       })
     ),
-    new Fetcher<{name: StringV, baseRate: NumberV, multiplier: NumberV, kink: NumberV, jump: NumberV}, InterestRateModelData>(`
-        #### JumpRateModel
 
-        * "JumpRateModel name:<String> baseRate:<Number> multiplier:<Number> kink:<Number> jump:<Number>" - The Jump interest rate
-        * E.g. "InterestRateModel Deploy JumpRateModel MyInterestRateModel 0.05 0.2 0.90 5" - 5% base rate and 20% utilization multiplier and 5x jump at 90% utilization
-      `,
-      "JumpRateModel",
-      [
-        new Arg("name", getStringV),
-        new Arg("baseRate", getExpNumberV),
-        new Arg("multiplier", getExpNumberV),
-        new Arg("kink", getExpNumberV),
-        new Arg("jump", getNumberV)
-      ],
-      async (world, {name, baseRate, multiplier, kink, jump}) => ({
-        invokation: await JumpRateModel.deploy<InterestRateModel>(world, from, [baseRate.val, multiplier.val, kink.val, jump.val]),
-        name: name.val,
-        contract: "JumpRateModel",
-        description: `JumpRate model baseRate=${baseRate.val} multiplier=${multiplier.val} kink=${kink.val} jump=${jump.val}`,
-        base: baseRate.encode().toString(),
-        slope: multiplier.encode().toString(),
-        kink: kink.encode().toString(),
-        jump: jump.encode().toString()
-      })
-    )
+    new Fetcher<{name: StringV, baseRate: NumberV, multiplier: NumberV, jump: NumberV, kink: NumberV}, InterestRateModelData>(`
+         #### JumpRateModel
+
+         * "JumpRateModel name:<String> baseRate:<Number> multiplier:<Number> jump:<Number> kink:<Number>" - The Jump interest rate
+           * E.g. "InterestRateModel Deploy JumpRateModel MyInterestRateModel 0.05 0.2 200 0.90" - 5% base rate and 20% utilization multiplier and 200% multiplier at 90% utilization
+       `,
+       "JumpRateModel",
+       [
+         new Arg("name", getStringV),
+         new Arg("baseRate", getExpNumberV),
+         new Arg("multiplier", getExpNumberV),
+         new Arg("jump", getExpNumberV),
+         new Arg("kink", getExpNumberV)
+       ],
+       async (world, {name, baseRate, multiplier, jump, kink}) => ({
+         invokation: await JumpRateModel.deploy<InterestRateModel>(world, from, [baseRate.encode(), multiplier.encode(), jump.encode(), kink.val]),
+         name: name.val,
+         contract: "JumpRateModel",
+         description: `JumpRateModel baseRate=${baseRate.encode().toString()} multiplier=${multiplier.encode().toString()} jump=${jump.encode().toString()} kink=${kink.encode().toString()}`,
+         base: baseRate.encode().toString(),
+         slope: multiplier.encode().toString(),
+         jump: jump.encode().toString(),
+         kink: kink.encode().toString()
+       })
+    ),
+
+    new Fetcher<{name: StringV, jump: NumberV, kink: NumberV, pot: AddressV, jug: AddressV}, InterestRateModelData>(`
+         #### DAIInterestRateModel
+
+         * "DAIInterestRateModel name:<String> jump:<Number> kink:<Number> pot:<Address> jug:<Address>" - The DAI interest rate model
+           * E.g. "InterestRateModel Deploy DAIInterestRateModel MyInterestRateModel 200 0.90 0xPotAddress 0xJugAddress" - 200% multiplier at 90% utilization
+       `,
+       "DAIInterestRateModel",
+       [
+         new Arg("name", getStringV),
+         new Arg("jump", getExpNumberV),
+         new Arg("kink", getExpNumberV),
+         new Arg("pot", getAddressV),
+         new Arg("jug", getAddressV)
+       ],
+       async (world, {name, jump, kink, pot, jug}) => ({
+         invokation: await DAIInterestRateModel.deploy<InterestRateModel>(world, from, [jump.encode(), kink.encode(), pot.val, jug.val]),
+         name: name.val,
+         contract: "DAIInterestRateModel",
+         description: `DAIInterestRateModel jump=${jump.encode().toString()} kink=${kink.encode().toString()} pot=${pot.val} jug=${jug.val}`,
+         jump: jump.encode().toString(),
+         kink: kink.encode().toString(),
+         pot: pot.val,
+         jug: jug.val
+       })
+     )
   ];
 
   let interestRateModelData = await getFetcherValue<any, InterestRateModelData>("DeployInterestRateModel", fetchers, world, event);
diff --git a/scenario/src/Contract/CToken.ts b/scenario/src/Contract/CToken.ts
index de002101d..81742a7e4 100644
--- a/scenario/src/Contract/CToken.ts
+++ b/scenario/src/Contract/CToken.ts
@@ -3,6 +3,7 @@ import { Callable, Sendable } from '../Invokation';
 import { encodedNumber } from '../Encoding';
 
 export interface CTokenMethods {
+  _resignImplementation(): Sendable<void>;
   balanceOfUnderlying(address: string): Callable<number>;
   borrowBalanceCurrent(address: string): Callable<string>;
   borrowBalanceStored(address: string): Callable<string>;
diff --git a/scenario/src/CoreEvent.ts b/scenario/src/CoreEvent.ts
index a13e14491..97c4791ed 100644
--- a/scenario/src/CoreEvent.ts
+++ b/scenario/src/CoreEvent.ts
@@ -212,7 +212,7 @@ export const commands = [
       new Arg('url', getStringV),
       new Arg('unlockedAccounts', getAddressV, { mapped: true })
     ],
-    (world, { url, unlockedAccounts }) => fork(world, url.val, unlockedAccounts.map(v => v.val))
+    async (world, { url, unlockedAccounts }) => fork(world, url.val, unlockedAccounts.map(v => v.val))
   ),
 
   new View<{ networkVal: StringV; }>(
diff --git a/scenario/src/Event/CTokenEvent.ts b/scenario/src/Event/CTokenEvent.ts
index 1e00dd0d6..71282faea 100644
--- a/scenario/src/Event/CTokenEvent.ts
+++ b/scenario/src/Event/CTokenEvent.ts
@@ -21,6 +21,7 @@ import {
   NumberV,
   StringV
 } from '../Value';
+import { getContract } from '../Contract';
 import { Arg, Command, View, processCommandEvent } from '../Command';
 import { CTokenErrorReporter } from '../ErrorReporter';
 import { getComptroller, getCTokenData } from '../ContractLookup';
@@ -288,17 +289,19 @@ async function setComptroller(world: World, from: string, cToken: CToken, comptr
   return world;
 }
 
-async function becomImplementation(
+async function becomeImplementation(
   world: World,
   from: string,
   cToken: CToken,
   becomeImplementationData: string
 ): Promise<World> {
+
+  const cErc20Delegate = getContract('CErc20Delegate');
+  const cErc20DelegateContract = await cErc20Delegate.at<CErc20Delegate>(world, cToken._address);
+
   let invokation = await invoke(
     world,
-    (cToken as CErc20Delegate).methods._becomeImplementation(
-      becomeImplementationData
-    ),
+    cErc20DelegateContract.methods._becomeImplementation(becomeImplementationData),
     from,
     CTokenErrorReporter
   );
@@ -315,6 +318,34 @@ async function becomImplementation(
   return world;
 }
 
+async function resignImplementation(
+  world: World,
+  from: string,
+  cToken: CToken,
+): Promise<World> {
+
+  const cErc20Delegate = getContract('CErc20Delegate');
+  const cErc20DelegateContract = await cErc20Delegate.at<CErc20Delegate>(world, cToken._address);
+
+  let invokation = await invoke(
+    world,
+    cErc20DelegateContract.methods._resignImplementation(),
+    from,
+    CTokenErrorReporter
+  );
+
+  world = addAction(
+    world,
+    `CToken ${cToken.name}: ${describeUser(
+      world,
+      from
+    )} initiates _resignImplementation.`,
+    invokation
+  );
+
+  return world;
+}
+
 async function setImplementation(
   world: World,
   from: string,
@@ -735,7 +766,7 @@ export function cTokenCommands() {
         new Arg('becomeImplementationData', getStringV)
       ],
       (world, from, { cToken, becomeImplementationData }) =>
-        becomImplementation(
+        becomeImplementation(
           world,
           from,
           cToken,
@@ -743,6 +774,23 @@ export function cTokenCommands() {
         ),
       { namePos: 1 }
     ),
+    new Command<{cToken: CToken;}>(
+      `
+        #### ResignImplementation
+
+        * "CToken <cToken> ResignImplementation"
+          * E.g. "CToken cDAI ResignImplementation"
+      `,
+      'ResignImplementation',
+      [new Arg('cToken', getCTokenV)],
+      (world, from, { cToken }) =>
+        resignImplementation(
+          world,
+          from,
+          cToken
+        ),
+      { namePos: 1 }
+    ),
     new Command<{
       cToken: CErc20Delegator;
       implementation: AddressV;
@@ -752,7 +800,7 @@ export function cTokenCommands() {
       `
         #### SetImplementation
 
-        * "CToken <cToken> SetImplementation implementation:<Address> allowResign:<Bool> becomImplementationData:<String>"
+        * "CToken <cToken> SetImplementation implementation:<Address> allowResign:<Bool> becomeImplementationData:<String>"
           * E.g. "CToken cDAI SetImplementation (CToken cDAIDelegate Address) True "0x01234anyByTeS56789"
       `,
       'SetImplementation',
diff --git a/scenario/src/Repl.ts b/scenario/src/Repl.ts
index 521c7e7c6..20ef2c18f 100644
--- a/scenario/src/Repl.ts
+++ b/scenario/src/Repl.ts
@@ -14,18 +14,21 @@ import {formatEvent} from './Formatter';
 import {complete} from './Completer';
 import {loadContracts} from './Networks';
 import {accountAliases, loadAccounts} from './Accounts';
-import {getNetworkPath} from './File';
+import {getNetworkPath, readFile} from './File';
 import {SuccessInvariant} from './Invariant/SuccessInvariant';
 import {createInterface} from './HistoricReadline';
 import {runCommand} from './Runner';
 import {parse} from './Parser';
-import { getSaddle } from 'eth-saddle';
+import {forkWeb3} from './Hypothetical';
+import {getSaddle} from 'eth-saddle';
+import Web3 from 'web3';
 
 import * as fs from 'fs';
 import * as path from 'path';
 
 const basePath = process.env.proj_root || process.cwd();
 const baseScenarioPath = path.join(basePath, 'spec', 'scenario');
+const baseNetworksPath = path.join(basePath, 'networks');
 
 function questionPromise(rl): Promise<string> {
   return new Promise((resolve, reject) => {
@@ -87,12 +90,12 @@ async function repl(): Promise<void> {
   });
 
   const verbose: boolean = !!process.env['verbose'];
-  let printer = new ReplPrinter(rl, verbose);
-
-  const saddle = await getSaddle(network);
+  const hypothetical: boolean = !!process.env['hypothetical'];
 
+  let printer = new ReplPrinter(rl, verbose);
   let contractInfo: string[];
 
+  let saddle = await getSaddle(network);
   let accounts: string[] = [saddle.account].concat(saddle.accounts).filter((x) => !!x);
 
   world = await initWorld(throwExpect, printer, saddle.web3, saddle, network, accounts, basePath);
@@ -104,6 +107,32 @@ async function repl(): Promise<void> {
 
   printer.printLine(`Network: ${network}`);
 
+  if (hypothetical) {
+    const forkJsonPath = path.join(baseNetworksPath, `${network}-fork.json`);
+    let forkJson;
+
+    try {
+      let forkJsonString = fs.readFileSync(forkJsonPath, 'utf8');
+      forkJson = JSON.parse(forkJsonString);
+    } catch (err) {
+      throw new Error(`Cannot read fork configuration from \`${forkJsonPath}\`, ${err}`);
+    }
+    if (!forkJson['url']) {
+      throw new Error(`Missing url in fork json`);
+    }
+    if (!forkJson['unlocked'] || !Array.isArray(forkJson.unlocked)) {
+      throw new Error(`Missing unlocked in fork json`);
+    }
+
+    saddle.web3 = await forkWeb3(saddle.web3, forkJson.url, forkJson.unlocked);
+    saddle.accounts = forkJson.unlocked;
+    console.log(`Running on fork ${forkJson.url} with unlocked accounts ${forkJson.unlocked.join(', ')}`)
+  } else {
+    // Uck, we have to load accounts first..let's just see if we have any unlocked accounts
+    // XXX does this break something with wallet addresses?
+    saddle.accounts = await (new Web3(saddle.web3.currentProvider)).eth.personal.getAccounts();
+  }
+
   if (saddle.accounts.length > 0) {
     printer.printLine(`Accounts:`);
     saddle.accounts.forEach((account, i) => {
@@ -123,23 +152,30 @@ async function repl(): Promise<void> {
   printer.printLine(``);
 
   if (script) {
-    printer.printLine(`Running script: ${script}...`);
-    const envVars = loadEnvVars();
-    const scriptData: string = fs.readFileSync(script).toString();
+    const combined = script.split(',').reduce((acc, script) => {
+      printer.printLine(`Running script: ${script}...`);
+      const envVars = loadEnvVars();
+      if (hypothetical) {
+        envVars['hypo'] = true;
+      }
+      const scriptData: string = fs.readFileSync(script).toString();
 
-    if (Object.keys(envVars).length > 0) {
-      printer.printLine(`Env Vars:`);
-    }
+      if (Object.keys(envVars).length > 0) {
+        printer.printLine(`Env Vars:`);
+      }
+
+      const replacedScript = Object.entries(envVars).reduce((data, [key, val]) => {
+        printer.printLine(`\t${key}: ${val}`);
 
-    const replacedScript = Object.entries(envVars).reduce((data, [key, val]) => {
-      printer.printLine(`\t${key}: ${val}`);
+        return data.split(`$${key}`).join(val);
+      }, scriptData);
 
-      return data.split(`$${key}`).join(val);
-    }, scriptData);
+      const finalScript = replacedScript.replace(new RegExp(/\$[\w_]+/, 'g'), 'Nothing');
 
-    const finalScript = replacedScript.replace(new RegExp(/\$[\w_]+/, 'g'), 'Nothing');
+      return [...acc, ...finalScript.split("\n")];
+    }, <string[]>[]);
 
-    return await finalScript.split("\n").reduce(async (acc, command) => {
+    return await combined.reduce(async (acc, command) => {
       return await runCommand(await acc, command, macros);
     }, Promise.resolve(world));
     printer.printLine(`Script complete.`);
diff --git a/scenario/src/World.ts b/scenario/src/World.ts
index 318a4d223..b883566aa 100644
--- a/scenario/src/World.ts
+++ b/scenario/src/World.ts
@@ -110,7 +110,7 @@ export class World extends Record(defaultWorldProps) {
     return {
       ...baseOpts,
       ...this.invokationOpts,
-      ...{ value: this.value ? this.value.toString() : undefined }
+      ...this.value ? {value: this.value.toString()} : {}
     };
   }
 
diff --git a/scenario/yarn.lock b/scenario/yarn.lock
index b61cf15b9..2e74e12ed 100644
--- a/scenario/yarn.lock
+++ b/scenario/yarn.lock
@@ -386,15 +386,25 @@
   resolved "https://registry.yarnpkg.com/@types/minimatch/-/minimatch-3.0.3.tgz#3dca0e3f33b200fc7d1139c0cd96c1268cadfd9d"
   integrity sha512-tHq6qdbT9U1IRSGf14CL0pUlULksvY9OZ+5eEgl1N7t+OA3tGvNpxJCzuKQlsNgCVwbAs670L1vcVQi8j9HjnA==
 
-"@types/node@*", "@types/node@^12.6.1":
+"@types/node@*":
   version "12.12.14"
   resolved "https://registry.yarnpkg.com/@types/node/-/node-12.12.14.tgz#1c1d6e3c75dba466e0326948d56e8bd72a1903d2"
   integrity sha512-u/SJDyXwuihpwjXy7hOOghagLEV1KdAST6syfnOk6QZAMzZuWZqXy5aYYZbh8Jdpd4escVFP0MvftHNDb9pruA==
 
-"@types/node@^10.12.18", "@types/node@^10.3.2":
-  version "10.17.6"
-  resolved "https://registry.yarnpkg.com/@types/node/-/node-10.17.6.tgz#1aaabd6f6470a6ac3824ab1e94d731ca1326d93d"
-  integrity sha512-0a2X6cgN3RdPBL2MIlR6Lt0KlM7fOFsutuXcdglcOq6WvLnYXgPQSh0Mx6tO1KCAE8MxbHSOSTWDoUxRq+l3DA==
+"@types/node@^10.12.18":
+  version "10.17.11"
+  resolved "https://registry.yarnpkg.com/@types/node/-/node-10.17.11.tgz#46ba035fb917b31c948280dbea22ab8838f386a4"
+  integrity sha512-dNd2pp8qTzzNLAs3O8nH3iU9DG9866KHq9L3ISPB7DOGERZN81nW/5/g/KzMJpCU8jrbCiMRBzV9/sCEdRosig==
+
+"@types/node@^10.3.2":
+  version "10.14.4"
+  resolved "https://registry.yarnpkg.com/@types/node/-/node-10.14.4.tgz#1c586b991457cbb58fef51bc4e0cfcfa347714b5"
+  integrity sha512-DT25xX/YgyPKiHFOpNuANIQIVvYEwCWXgK2jYYwqgaMrYE6+tq+DtmMwlD3drl6DJbUwtlIDnn0d7tIn/EbXBg==
+
+"@types/node@^12.6.1":
+  version "12.12.21"
+  resolved "https://registry.yarnpkg.com/@types/node/-/node-12.12.21.tgz#aa44a6363291c7037111c47e4661ad210aded23f"
+  integrity sha512-8sRGhbpU+ck1n0PGAUgVrWrWdjSW2aqNeyC15W88GRsMpSwzv6RJGlLhE7s2RhVSOdyDmxbqlWSeThq4/7xqlA==
 
 "@types/prop-types@*":
   version "15.7.3"
@@ -2358,11 +2368,6 @@ copy-props@^2.0.1:
     each-props "^1.3.0"
     is-plain-object "^2.0.1"
 
-core-js-pure@^3.0.1:
-  version "3.6.4"
-  resolved "https://registry.yarnpkg.com/core-js-pure/-/core-js-pure-3.6.4.tgz#4bf1ba866e25814f149d4e9aaa08c36173506e3a"
-  integrity sha512-epIhRLkXdgv32xIUFaaAry2wdxZYBi6bgM7cB136dzzXXa+dFyRLTZeLUJxnd8ShrmyVXBub63n2NHo2JAt8Cw==
-
 core-js@^2.4.0, core-js@^2.5.0:
   version "2.6.10"
   resolved "https://registry.yarnpkg.com/core-js/-/core-js-2.6.10.tgz#8a5b8391f8cc7013da703411ce5b585706300d7f"
@@ -2902,23 +2907,6 @@ error-ex@^1.2.0:
   dependencies:
     is-arrayish "^0.2.1"
 
-es-abstract@^1.17.0-next.1:
-  version "1.17.2"
-  resolved "https://registry.yarnpkg.com/es-abstract/-/es-abstract-1.17.2.tgz#965b10af56597b631da15872c17a405e86c1fd46"
-  integrity sha512-YoKuru3Lyoy7yVTBSH2j7UxTqe/je3dWAruC0sHvZX1GNd5zX8SSLvQqEgO9b3Ex8IW+goFI9arEEsFIbulhOw==
-  dependencies:
-    es-to-primitive "^1.2.1"
-    function-bind "^1.1.1"
-    has "^1.0.3"
-    has-symbols "^1.0.1"
-    is-callable "^1.1.5"
-    is-regex "^1.0.5"
-    object-inspect "^1.7.0"
-    object-keys "^1.1.1"
-    object.assign "^4.1.0"
-    string.prototype.trimleft "^2.1.1"
-    string.prototype.trimright "^2.1.1"
-
 es-abstract@^1.5.0:
   version "1.16.3"
   resolved "https://registry.yarnpkg.com/es-abstract/-/es-abstract-1.16.3.tgz#52490d978f96ff9f89ec15b5cf244304a5bca161"
@@ -3194,10 +3182,10 @@ eth-query@^2.0.2, eth-query@^2.1.0, eth-query@^2.1.2:
     json-rpc-random-id "^1.0.0"
     xtend "^4.0.1"
 
-eth-saddle@^0.0.25:
-  version "0.0.25"
-  resolved "https://registry.yarnpkg.com/eth-saddle/-/eth-saddle-0.0.25.tgz#a047779de227ee30314a3024e2162dff9a710b9d"
-  integrity sha512-lAF//N9OXqw/hkV7kga3vXtckz8mBN18wqYGkGT2y1a3P71DnTbi+ni9VZlN+CBUKLKRCQyJDVd3BnmbLTI5yQ==
+eth-saddle@^0.0.30:
+  version "0.0.30"
+  resolved "https://registry.yarnpkg.com/eth-saddle/-/eth-saddle-0.0.30.tgz#9be303d4155e6482c098664fef43f812034a23dc"
+  integrity sha512-0KR/yurqQX3ZgD7QJwHyAK51lPLIaPfMUvkeUUos08btz0UlblnR+p2IJ2hR3Nkemu8rnBiKH3y39o/rGkEJ6w==
   dependencies:
     "@0x/subproviders" "^6.0.0"
     "@compound-finance/sol-coverage" "^4.0.0-r1"
@@ -3300,7 +3288,7 @@ ethereumjs-abi@0.6.7:
     bn.js "^4.11.8"
     ethereumjs-util "^6.0.0"
 
-ethereumjs-account@3.0.0, ethereumjs-account@^3.0.0:
+ethereumjs-account@3.0.0:
   version "3.0.0"
   resolved "https://registry.yarnpkg.com/ethereumjs-account/-/ethereumjs-account-3.0.0.tgz#728f060c8e0c6e87f1e987f751d3da25422570a9"
   integrity sha512-WP6BdscjiiPkQfF9PVfMcwx/rDvfZTjFKY0Uwc09zSQr9JfIVH87dYIJu0gNhBhpmovV4yq295fdllS925fnBA==
@@ -3318,7 +3306,7 @@ ethereumjs-account@^2.0.3:
     rlp "^2.0.0"
     safe-buffer "^5.1.1"
 
-ethereumjs-block@2.2.0:
+ethereumjs-block@2.2.0, ethereumjs-block@~2.2.0:
   version "2.2.0"
   resolved "https://registry.yarnpkg.com/ethereumjs-block/-/ethereumjs-block-2.2.0.tgz#8c6c3ab4a5eff0a16d9785fbeedbe643f4dbcbef"
   integrity sha512-Ye+uG/L2wrp364Zihdlr/GfC3ft+zG8PdHcRtsBFNNH1CkOhxOwdB8friBU85n89uRZ9eIMAywCq0F4CwT1wAw==
@@ -3329,17 +3317,6 @@ ethereumjs-block@2.2.0:
     ethereumjs-util "^5.0.0"
     merkle-patricia-tree "^2.1.2"
 
-ethereumjs-block@2.2.1, ethereumjs-block@~2.2.0:
-  version "2.2.1"
-  resolved "https://registry.yarnpkg.com/ethereumjs-block/-/ethereumjs-block-2.2.1.tgz#5fba423305b40ab6486a6b81922e5312b2667c8d"
-  integrity sha512-ze8I1844m5oKZL7hiHuezRcPzqdi4Iv0ssqQyuRaJ9Je0/YCYfXobJHvNLnex2ETgs5JypicdtLYrCNWdgcLvg==
-  dependencies:
-    async "^2.0.1"
-    ethereumjs-common "^1.1.0"
-    ethereumjs-tx "^2.1.1"
-    ethereumjs-util "^5.0.0"
-    merkle-patricia-tree "^2.1.2"
-
 ethereumjs-block@^1.2.2, ethereumjs-block@^1.4.1, ethereumjs-block@^1.6.0:
   version "1.7.1"
   resolved "https://registry.yarnpkg.com/ethereumjs-block/-/ethereumjs-block-1.7.1.tgz#78b88e6cc56de29a6b4884ee75379b6860333c3f"
@@ -3351,17 +3328,6 @@ ethereumjs-block@^1.2.2, ethereumjs-block@^1.4.1, ethereumjs-block@^1.6.0:
     ethereumjs-util "^5.0.0"
     merkle-patricia-tree "^2.1.2"
 
-ethereumjs-block@^2.2.1, ethereumjs-block@~2.2.2:
-  version "2.2.2"
-  resolved "https://registry.yarnpkg.com/ethereumjs-block/-/ethereumjs-block-2.2.2.tgz#c7654be7e22df489fda206139ecd63e2e9c04965"
-  integrity sha512-2p49ifhek3h2zeg/+da6XpdFR3GlqY3BIEiqxGF8j9aSRIgkb7M1Ky+yULBKJOu8PAZxfhsYA+HxUk2aCQp3vg==
-  dependencies:
-    async "^2.0.1"
-    ethereumjs-common "^1.5.0"
-    ethereumjs-tx "^2.1.1"
-    ethereumjs-util "^5.0.0"
-    merkle-patricia-tree "^2.1.2"
-
 ethereumjs-blockchain@^3.4.0:
   version "3.4.0"
   resolved "https://registry.yarnpkg.com/ethereumjs-blockchain/-/ethereumjs-blockchain-3.4.0.tgz#92240da6ecd86b3d8d324df69510b381f26c966b"
@@ -3378,28 +3344,12 @@ ethereumjs-blockchain@^3.4.0:
     safe-buffer "^5.1.2"
     semaphore "^1.1.0"
 
-ethereumjs-blockchain@^4.0.2:
-  version "4.0.3"
-  resolved "https://registry.yarnpkg.com/ethereumjs-blockchain/-/ethereumjs-blockchain-4.0.3.tgz#e013034633a30ad2006728e8e2b21956b267b773"
-  integrity sha512-0nJWbyA+Gu0ZKZr/cywMtB/77aS/4lOVsIKbgUN2sFQYscXO5rPbUfrEe7G2Zhjp86/a0VqLllemDSTHvx3vZA==
-  dependencies:
-    async "^2.6.1"
-    ethashjs "~0.0.7"
-    ethereumjs-block "~2.2.2"
-    ethereumjs-common "^1.5.0"
-    ethereumjs-util "~6.1.0"
-    flow-stoplight "^1.0.0"
-    level-mem "^3.0.1"
-    lru-cache "^5.1.1"
-    rlp "^2.2.2"
-    semaphore "^1.1.0"
-
-ethereumjs-common@1.4.0, ethereumjs-common@^1.1.0, ethereumjs-common@^1.3.1, ethereumjs-common@^1.3.2:
+ethereumjs-common@^1.1.0:
   version "1.4.0"
   resolved "https://registry.yarnpkg.com/ethereumjs-common/-/ethereumjs-common-1.4.0.tgz#a940685f88f3c2587e4061630fe720b089c965b8"
   integrity sha512-ser2SAplX/YI5W2AnzU8wmSjKRy4KQd4uxInJ36BzjS3m18E/B9QedPUIresZN1CSEQb/RgNQ2gN7C/XbpTafA==
 
-ethereumjs-common@^1.5.0:
+ethereumjs-common@^1.3.1, ethereumjs-common@^1.3.2:
   version "1.5.0"
   resolved "https://registry.yarnpkg.com/ethereumjs-common/-/ethereumjs-common-1.5.0.tgz#d3e82fc7c47c0cef95047f431a99485abc9bb1cd"
   integrity sha512-SZOjgK1356hIY7MRj3/ma5qtfr/4B5BL+G4rP/XSMYr2z1H5el4RX5GReYCKmQmYI/nSBmRnwrZ17IfHuG0viQ==
@@ -3412,7 +3362,7 @@ ethereumjs-tx@1.3.7, ethereumjs-tx@^1.1.1, ethereumjs-tx@^1.2.0, ethereumjs-tx@^
     ethereum-common "^0.0.18"
     ethereumjs-util "^5.0.0"
 
-ethereumjs-tx@2.1.1, ethereumjs-tx@^2.1.1:
+ethereumjs-tx@^2.1.1:
   version "2.1.1"
   resolved "https://registry.yarnpkg.com/ethereumjs-tx/-/ethereumjs-tx-2.1.1.tgz#7d204e2b319156c9bc6cec67e9529424a26e8ccc"
   integrity sha512-QtVriNqowCFA19X9BCRPMgdVNJ0/gMBS91TQb1DfrhsbR748g4STwxZptFAwfqehMyrF8rDwB23w87PQwru0wA==
@@ -3420,7 +3370,7 @@ ethereumjs-tx@2.1.1, ethereumjs-tx@^2.1.1:
     ethereumjs-common "^1.3.1"
     ethereumjs-util "^6.0.0"
 
-ethereumjs-util@6.1.0, ethereumjs-util@~6.1.0:
+ethereumjs-util@6.1.0:
   version "6.1.0"
   resolved "https://registry.yarnpkg.com/ethereumjs-util/-/ethereumjs-util-6.1.0.tgz#e9c51e5549e8ebd757a339cc00f5380507e799c8"
   integrity sha512-URESKMFbDeJxnAxPppnk2fN6Y3BIatn9fwn76Lm8bQlt+s52TpG8dN9M66MLPuRAiAOIqL3dfwqWJf0sd0fL0Q==
@@ -3501,27 +3451,6 @@ ethereumjs-vm@3.0.0:
     rustbn.js "~0.2.0"
     safe-buffer "^5.1.1"
 
-ethereumjs-vm@4.1.1:
-  version "4.1.1"
-  resolved "https://registry.yarnpkg.com/ethereumjs-vm/-/ethereumjs-vm-4.1.1.tgz#ba6f565fd7788a0e7db494fa2096d45f9ea0802b"
-  integrity sha512-Bh2avDY9Hyon9TvJ/fmkdyd5JDnmTudLJ5oKhmTfXn0Jjq7UzP4YRNp7e5PWoWXSmdXAGXU9W0DXK5TV9Qy/NQ==
-  dependencies:
-    async "^2.1.2"
-    async-eventemitter "^0.2.2"
-    core-js-pure "^3.0.1"
-    ethereumjs-account "^3.0.0"
-    ethereumjs-block "^2.2.1"
-    ethereumjs-blockchain "^4.0.2"
-    ethereumjs-common "^1.3.2"
-    ethereumjs-tx "^2.1.1"
-    ethereumjs-util "~6.1.0"
-    fake-merkle-patricia-tree "^1.0.1"
-    functional-red-black-tree "^1.0.1"
-    merkle-patricia-tree "^2.3.2"
-    rustbn.js "~0.2.0"
-    safe-buffer "^5.1.1"
-    util.promisify "^1.0.0"
-
 ethereumjs-vm@^2.1.0, ethereumjs-vm@^2.3.4, ethereumjs-vm@^2.6.0:
   version "2.6.0"
   resolved "https://registry.yarnpkg.com/ethereumjs-vm/-/ethereumjs-vm-2.6.0.tgz#76243ed8de031b408793ac33907fb3407fe400c6"
@@ -4084,7 +4013,7 @@ functional-red-black-tree@^1.0.1, functional-red-black-tree@~1.0.1:
   resolved "https://registry.yarnpkg.com/functional-red-black-tree/-/functional-red-black-tree-1.0.1.tgz#1b0ab3bd553b2a0d6399d29c0e3ea0b252078327"
   integrity sha1-GwqzvVU7Kg1jmdKcDj6gslIHgyc=
 
-ganache-core@^2.6.0:
+ganache-core@^2.6.0, ganache-core@^2.8.0:
   version "2.8.0"
   resolved "https://registry.yarnpkg.com/ganache-core/-/ganache-core-2.8.0.tgz#eeadc7f7fc3a0c20d99f8f62021fb80b5a05490c"
   integrity sha512-hfXqZGJx700jJqwDHNXrU2BnPYuETn1ekm36oRHuXY3oOuJLFs5C+cFdUFaBlgUxcau1dOgZUUwKqTAy0gTA9Q==
@@ -4117,39 +4046,6 @@ ganache-core@^2.6.0:
     ethereumjs-wallet "0.6.3"
     web3 "1.2.1"
 
-"ganache-core@https://github.com/trufflesuite/ganache-core.git":
-  version "2.9.1"
-  resolved "https://github.com/trufflesuite/ganache-core.git#dad69a5a19ecafb656994df6971f9a75e6ac35a2"
-  dependencies:
-    abstract-leveldown "3.0.0"
-    async "2.6.2"
-    bip39 "2.5.0"
-    cachedown "1.0.0"
-    clone "2.1.2"
-    debug "3.2.6"
-    encoding-down "5.0.4"
-    eth-sig-util "2.3.0"
-    ethereumjs-abi "0.6.7"
-    ethereumjs-account "3.0.0"
-    ethereumjs-block "2.2.1"
-    ethereumjs-common "1.4.0"
-    ethereumjs-tx "2.1.1"
-    ethereumjs-util "6.1.0"
-    ethereumjs-vm "4.1.1"
-    heap "0.2.6"
-    level-sublevel "6.6.4"
-    levelup "3.1.1"
-    lodash "4.17.14"
-    merkle-patricia-tree "2.3.2"
-    seedrandom "3.0.1"
-    source-map-support "0.5.12"
-    tmp "0.1.0"
-    web3-provider-engine "14.2.1"
-    websocket "1.0.29"
-  optionalDependencies:
-    ethereumjs-wallet "0.6.3"
-    web3 "1.2.4"
-
 gauge@~2.7.3:
   version "2.7.4"
   resolved "https://registry.yarnpkg.com/gauge/-/gauge-2.7.4.tgz#2c03405c7538c39d7eb37b317022e325fb018bf7"
@@ -4860,11 +4756,6 @@ is-callable@^1.1.3, is-callable@^1.1.4:
   resolved "https://registry.yarnpkg.com/is-callable/-/is-callable-1.1.4.tgz#1e1adf219e1eeb684d691f9d6a05ff0d30a24d75"
   integrity sha512-r5p9sxJjYnArLjObpjA4xu5EKI3CuKHkJXMhT7kwbpUyIFD1n5PMAsoPvWnvtZiNz7LjkYDRZhd7FlI0eMijEA==
 
-is-callable@^1.1.5:
-  version "1.1.5"
-  resolved "https://registry.yarnpkg.com/is-callable/-/is-callable-1.1.5.tgz#f7e46b596890456db74e7f6e976cb3273d06faab"
-  integrity sha512-ESKv5sMCJB2jnHTWZ3O5itG+O128Hsus4K4Qh1h2/cgn2vbgnLSVqfV46AeJA9D5EeeLa9w81KUXMtn34zhX+Q==
-
 is-data-descriptor@^0.1.4:
   version "0.1.4"
   resolved "https://registry.yarnpkg.com/is-data-descriptor/-/is-data-descriptor-0.1.4.tgz#0b5ee648388e2c860282e793f1856fec3f301b56"
@@ -5018,13 +4909,6 @@ is-regex@^1.0.4:
   dependencies:
     has "^1.0.1"
 
-is-regex@^1.0.5:
-  version "1.0.5"
-  resolved "https://registry.yarnpkg.com/is-regex/-/is-regex-1.0.5.tgz#39d589a358bf18967f726967120b8fc1aed74eae"
-  integrity sha512-vlKW17SNq44owv5AQR3Cq0bQPEb8+kF3UKZ2fiZNOWtztYE5i0CzCZxFDwO58qAOWtxdBRVO/V5Qin1wjCqFYQ==
-  dependencies:
-    has "^1.0.3"
-
 is-relative@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/is-relative/-/is-relative-1.0.0.tgz#a1bb6935ce8c5dba1e8b9754b9b2dcc020e2260d"
@@ -6349,7 +6233,7 @@ object-visit@^1.0.0:
   dependencies:
     isobject "^3.0.0"
 
-object.assign@^4.0.4, object.assign@^4.1.0:
+object.assign@^4.0.4:
   version "4.1.0"
   resolved "https://registry.yarnpkg.com/object.assign/-/object.assign-4.1.0.tgz#968bf1100d7956bb3ca086f006f846b3bc4008da"
   integrity sha512-exHJeq6kBKj58mqGyTQ9DFvrZC/eR6OwxzoM9YRoGBqrXYonaFyGiFMuc9VZrXf7DarreEwMpurG3dd+CNyW5w==
@@ -6369,14 +6253,6 @@ object.defaults@^1.0.0, object.defaults@^1.1.0:
     for-own "^1.0.0"
     isobject "^3.0.0"
 
-object.getownpropertydescriptors@^2.0.3:
-  version "2.1.0"
-  resolved "https://registry.yarnpkg.com/object.getownpropertydescriptors/-/object.getownpropertydescriptors-2.1.0.tgz#369bf1f9592d8ab89d712dced5cb81c7c5352649"
-  integrity sha512-Z53Oah9A3TdLoblT7VKJaTDdXdT+lQO+cNpKVnya5JDe9uLvzu1YyY1yFDFrcxrlRgWrEFH0jJtD/IbuwjcEVg==
-  dependencies:
-    define-properties "^1.1.3"
-    es-abstract "^1.17.0-next.1"
-
 object.map@^1.0.0:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/object.map/-/object.map-1.0.1.tgz#cf83e59dc8fcc0ad5f4250e1f78b3b81bd801d37"
@@ -7386,7 +7262,7 @@ ripemd160@^2.0.0, ripemd160@^2.0.1:
     hash-base "^3.0.0"
     inherits "^2.0.1"
 
-rlp@^2.0.0, rlp@^2.2.1, rlp@^2.2.2, rlp@^2.2.3:
+rlp@^2.0.0, rlp@^2.2.1, rlp@^2.2.3:
   version "2.2.4"
   resolved "https://registry.yarnpkg.com/rlp/-/rlp-2.2.4.tgz#d6b0e1659e9285fc509a5d169a9bd06f704951c1"
   integrity sha512-fdq2yYCWpAQBhwkZv+Z8o/Z4sPmYm1CUq6P7n6lVTOdb949CnqA0sndXal5C1NleSVSZm6q5F3iEbauyVln/iw==
@@ -7979,14 +7855,6 @@ string.prototype.trim@~1.1.2:
     function-bind "^1.0.2"
 
 string.prototype.trimleft@^2.1.0:
-  version "2.1.0"
-  resolved "https://registry.yarnpkg.com/string.prototype.trimleft/-/string.prototype.trimleft-2.1.0.tgz#6cc47f0d7eb8d62b0f3701611715a3954591d634"
-  integrity sha512-FJ6b7EgdKxxbDxc79cOlok6Afd++TTs5szo+zJTUyow3ycrRfJVE2pq3vcN53XexvKZu/DJMDfeI/qMiZTrjTw==
-  dependencies:
-    define-properties "^1.1.3"
-    function-bind "^1.1.1"
-
-string.prototype.trimleft@^2.1.1:
   version "2.1.1"
   resolved "https://registry.yarnpkg.com/string.prototype.trimleft/-/string.prototype.trimleft-2.1.1.tgz#9bdb8ac6abd6d602b17a4ed321870d2f8dcefc74"
   integrity sha512-iu2AGd3PuP5Rp7x2kEZCrB2Nf41ehzh+goo8TV7z8/XDBbsvc6HQIlUl9RjkZ4oyrW1XM5UwlGl1oVEaDjg6Ag==
@@ -7995,14 +7863,6 @@ string.prototype.trimleft@^2.1.1:
     function-bind "^1.1.1"
 
 string.prototype.trimright@^2.1.0:
-  version "2.1.0"
-  resolved "https://registry.yarnpkg.com/string.prototype.trimright/-/string.prototype.trimright-2.1.0.tgz#669d164be9df9b6f7559fa8e89945b168a5a6c58"
-  integrity sha512-fXZTSV55dNBwv16uw+hh5jkghxSnc5oHq+5K/gXgizHwAvMetdAJlHqqoFC1FSDVPYWLkAKl2cxpUT41sV7nSg==
-  dependencies:
-    define-properties "^1.1.3"
-    function-bind "^1.1.1"
-
-string.prototype.trimright@^2.1.1:
   version "2.1.1"
   resolved "https://registry.yarnpkg.com/string.prototype.trimright/-/string.prototype.trimright-2.1.1.tgz#440314b15996c866ce8a0341894d45186200c5d9"
   integrity sha512-qFvWL3/+QIgZXVmJBfpHmxLB7xsUXz6HsUmP8+5dRaC3Q7oKUv9Vo6aMCRZC1smrtyECFsIT30PqBJ1gTjAs+g==
@@ -8715,14 +8575,6 @@ util-deprecate@^1.0.1, util-deprecate@~1.0.1:
   resolved "https://registry.yarnpkg.com/util-deprecate/-/util-deprecate-1.0.2.tgz#450d4dc9fa70de732762fbd2d4a28981419a0ccf"
   integrity sha1-RQ1Nyfpw3nMnYvvS1KKJgUGaDM8=
 
-util.promisify@^1.0.0:
-  version "1.0.0"
-  resolved "https://registry.yarnpkg.com/util.promisify/-/util.promisify-1.0.0.tgz#440f7165a459c9a16dc145eb8e72f35687097030"
-  integrity sha512-i+6qA2MPhvoKLuxnJNpXAGhg7HphQOSUq2LKMZD0m15EiskXUkMvKdF4Uui0WYeCUGea+o2cw/ZuwehtfsrNkA==
-  dependencies:
-    define-properties "^1.1.2"
-    object.getownpropertydescriptors "^2.0.3"
-
 util@0.10.3:
   version "0.10.3"
   resolved "https://registry.yarnpkg.com/util/-/util-0.10.3.tgz#7afb1afe50805246489e3db7fe0ed379336ac0f9"
@@ -9399,7 +9251,7 @@ web3@1.2.1:
     web3-shh "1.2.1"
     web3-utils "1.2.1"
 
-web3@1.2.4, web3@^1.2.4:
+web3@^1.2.4:
   version "1.2.4"
   resolved "https://registry.yarnpkg.com/web3/-/web3-1.2.4.tgz#6e7ab799eefc9b4648c2dab63003f704a1d5e7d9"
   integrity sha512-xPXGe+w0x0t88Wj+s/dmAdASr3O9wmA9mpZRtixGZxmBexAF0MjfqYM+MS4tVl5s11hMTN3AZb8cDD4VLfC57A==
diff --git a/spec/scenario/MCDai.scen b/spec/scenario/MCDai.scen
index 7387c149b..73b0b6880 100644
--- a/spec/scenario/MCDai.scen
+++ b/spec/scenario/MCDai.scen
@@ -1,6 +1,8 @@
 -- Multi-collateral DAI tests
+-- These fork tests are very slow and highly dependent on ganache version, so we mark them pending
 
 Macro ForkMCD
+    -- Uses MakerDAO 0.2.16 Release https://changelog.makerdao.com/releases/kovan/0.2.16/index.html
     Alias CTokenAdmin "0x9C1856636d78C051deAd6CAB9c5699e4E25549e9"
     Alias DaiHolder "0x9Bffd1579bd6760a186fFf1A720f2a5dB35dE0f4"
     Alias DaiAddress "0xc27a24e60a89a03bd2f1ffb4ea59076fd8385fe6"
@@ -11,6 +13,16 @@ Macro ForkMCD
     Erc20 Deploy Existing DAI DaiAddress DAI
     Assert Equal (EtherBalance CTokenAdmin) 1.680448935e18 -- Ensure the fork works as expected
 
+Macro ForkMCD101
+    -- Uses MakerDAO 1.0.1 Release https://changelog.makerdao.com/releases/kovan/1.0.1/index.html
+    Alias CTokenAdmin "0xA776184Fd6F545DAe5f51361dBcC9018549a9749"
+    Alias DaiHolder "0x72776bb917751225d24c07d0663b3780b2ada67c"
+    Alias DaiJoinAddress "0x5aa71a3ae1c0bd6ac27a1f28e1415fffb6f15b8c"
+    Alias PotAddress "0xea190dbdc7adf265260ec4da6e9675fd4f5a78bb"
+    Alias VatAddress "0xba987bdb501d131f766fee8180da5d81b34b69d9"
+    Alias JugAddress "0xcbb7718c9f39d05aeede1c472ca8bf804b2f1ead"
+    Web3Fork "https://kovan.infura.io/v3/e1a5d4d2c06a4e81945fca56d0d5d8ea@15090204" (CTokenAdmin DaiHolder)
+
 Macro DeployCDAIWithDSR
     ForkMCD
     NewComptroller
@@ -87,22 +99,70 @@ Macro CheckBasicBorrowRepayWithDSR repayAmount=1000015000000000000
     Assert Approx (MCD PotAt PotAddress "pie" (CToken cDAI Address)) repayAmount         -- pot is a wad (1e18), check for ~ 1 DAI + interest
     Assert (MCD VatAt VatAddress "dai" (CToken cDAI Address)) LessThan 2e27              -- vat is a rad (1e45), check for ~ dust
 
-Test "Basic mint and redeem cDAI2 (directly to swept DSR)"
+Pending "Basic mint and redeem cDAI2 (directly to swept DSR)"
     DeployCDAIWithDSR
     CheckBasicMintRedeemWithDSR
 
-Test "Basic borrow and repay cDAI2 (directly to swept DSR)"
+Pending "Basic borrow and repay cDAI2 (directly to swept DSR)"
     DeployCDAIWithDSR
     CheckBasicBorrowRepayWithDSR
 
-Test "Basic mint and redeem cDAI2 (upgrade to swept DSR)"
+Pending "Basic mint and redeem cDAI2 (upgrade to swept DSR)"
     DeployCDAI
     CheckBasicMintRedeem
     UpgradeToDSR
     CheckBasicMintRedeemWithDSR
 
-Test "Basic borrow and repay cDAI2 (upgrade to swept DSR)"
+Pending "Basic borrow and repay cDAI2 (upgrade to swept DSR)"
     DeployCDAI
     CheckBasicMintRedeem
     UpgradeToDSR
     CheckBasicBorrowRepayWithDSR repayAmount:1000014999999999999 -- real block numbers can get nasty
+
+Pending "Mint, upgrade to DSR and then downgrade to vanilla delegate"
+    DeployCDAI
+    From DaiHolder (Erc20 DAI Approve (CToken cDAI Address) 1e18)
+    Mint DaiHolder 1e18 cDAI
+    Assert Equal (Erc20 DAI TokenBalance cDAI) 1e18
+    Assert Equal (CToken cDAI Cash) 1e18
+    -- Upgrade
+    UpgradeToDSR
+    Assert Equal (Erc20 DAI TokenBalance cDAI) 0
+    Assert Approx (CToken cDAI Cash) 1e18
+    Assert Approx (MCD PotAt PotAddress "pie" (CToken cDAI Address)) 1e18
+    -- Downgrade
+    From CTokenAdmin (CToken cDAI SetImplementation (CTokenDelegate cErc20Delegate Address) True "0x0")
+    Assert Approx (Erc20 DAI TokenBalance cDAI) 1e18
+    Assert Approx (CToken cDAI Cash) 1e18
+
+Pending "Mint, upgrade to DSR, mint, and then reupgrade to a new cdai delegate"
+    DeployCDAI
+    From DaiHolder (Erc20 DAI Approve (CToken cDAI Address) 2e18)
+    Mint DaiHolder 1e18 cDAI
+    Assert Equal (Erc20 DAI TokenBalance cDAI) 1e18
+    Assert Equal (CToken cDAI Cash) 1e18
+    -- Upgrade
+    UpgradeToDSR
+    Mint DaiHolder 1e18 cDAI
+    Assert Equal (Erc20 DAI TokenBalance cDAI) 0
+    Assert Approx (CToken cDAI Cash) 2e18
+    Assert Approx (MCD PotAt PotAddress "pie" (CToken cDAI Address)) 2e18
+    -- Reupgrade to a new cDaiDelegate
+    CTokenDelegate Deploy CDaiDelegate cDaiDelegate2
+    From CTokenAdmin (CToken cDAI SetImplementation (CTokenDelegate cDaiDelegate2 Address) True (EncodeParameters ("address" "address") (DaiJoinAddress PotAddress)))
+    Assert Equal (Erc20 DAI TokenBalance cDAI) 0
+    Assert Approx (CToken cDAI Cash) 2e18
+    Assert Approx (MCD PotAt PotAddress "pie" (CToken cDAI Address)) 2e18
+
+Pending "Test resigning implementation"
+    ForkMCD101
+    UseConfigs kovan
+    Assert Approx (Erc20 DAI TokenBalance cDAI) 0
+    Assert Equal (MCD PotAt PotAddress "pie" (CToken cDAI Address)) 137889496810499277888
+    From CTokenAdmin (CToken cDAI ResignImplementation)
+    Assert Approx (Erc20 DAI TokenBalance cDAI) 137889496810499277888
+    Assert Approx (MCD PotAt PotAddress "pie" (CToken cDAI Address)) 0
+
+Pending "DAI interest rate model"
+    ForkMCD101
+    InterestRateModel Deploy DAIInterestRateModel DSR_Kink_9000bps_Jump_12000bps_AssumedRF_500bps 120e16 90e16 PotAddress JugAddress
diff --git a/yarn.lock b/yarn.lock
index bb0a2967e..5cc1e8ffc 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3372,11 +3372,6 @@ core-js-compat@^3.4.7:
     browserslist "^4.8.0"
     semver "^6.3.0"
 
-core-js-pure@^3.0.1:
-  version "3.4.7"
-  resolved "https://registry.yarnpkg.com/core-js-pure/-/core-js-pure-3.4.7.tgz#c998e1892da9949200c7452cbd33c0df95be9f54"
-  integrity sha512-Am3uRS8WCdTFA3lP7LtKR0PxgqYzjAMGKXaZKSNSC/8sqU0Wfq8R/YzoRs2rqtOVEunfgH+0q3O0BKOg0AvjPw==
-
 core-js@^2.4.0, core-js@^2.5.0:
   version "2.6.10"
   resolved "https://registry.yarnpkg.com/core-js/-/core-js-2.6.10.tgz#8a5b8391f8cc7013da703411ce5b585706300d7f"
@@ -3984,7 +3979,24 @@ error-ex@^1.2.0, error-ex@^1.3.1:
   dependencies:
     is-arrayish "^0.2.1"
 
-es-abstract@^1.5.0, es-abstract@^1.5.1:
+es-abstract@^1.17.0-next.1:
+  version "1.17.0-next.1"
+  resolved "https://registry.yarnpkg.com/es-abstract/-/es-abstract-1.17.0-next.1.tgz#94acc93e20b05a6e96dacb5ab2f1cb3a81fc2172"
+  integrity sha512-7MmGr03N7Rnuid6+wyhD9sHNE2n4tFSwExnU2lQl3lIo2ShXWGePY80zYaoMOmILWv57H0amMjZGHNzzGG70Rw==
+  dependencies:
+    es-to-primitive "^1.2.1"
+    function-bind "^1.1.1"
+    has "^1.0.3"
+    has-symbols "^1.0.1"
+    is-callable "^1.1.4"
+    is-regex "^1.0.4"
+    object-inspect "^1.7.0"
+    object-keys "^1.1.1"
+    object.assign "^4.1.0"
+    string.prototype.trimleft "^2.1.0"
+    string.prototype.trimright "^2.1.0"
+
+es-abstract@^1.5.0:
   version "1.16.3"
   resolved "https://registry.yarnpkg.com/es-abstract/-/es-abstract-1.16.3.tgz#52490d978f96ff9f89ec15b5cf244304a5bca161"
   integrity sha512-WtY7Fx5LiOnSYgF5eg/1T+GONaGmpvpPdCpSnYij+U2gDTL0UPfWrhDw7b2IYb+9NQJsYpCA0wOQvZfsd6YwRw==
@@ -4261,10 +4273,10 @@ eth-query@^2.0.2, eth-query@^2.1.0, eth-query@^2.1.2:
     json-rpc-random-id "^1.0.0"
     xtend "^4.0.1"
 
-eth-saddle@^0.0.25:
-  version "0.0.25"
-  resolved "https://registry.yarnpkg.com/eth-saddle/-/eth-saddle-0.0.25.tgz#a047779de227ee30314a3024e2162dff9a710b9d"
-  integrity sha512-lAF//N9OXqw/hkV7kga3vXtckz8mBN18wqYGkGT2y1a3P71DnTbi+ni9VZlN+CBUKLKRCQyJDVd3BnmbLTI5yQ==
+eth-saddle@^0.0.30:
+  version "0.0.30"
+  resolved "https://registry.yarnpkg.com/eth-saddle/-/eth-saddle-0.0.30.tgz#9be303d4155e6482c098664fef43f812034a23dc"
+  integrity sha512-0KR/yurqQX3ZgD7QJwHyAK51lPLIaPfMUvkeUUos08btz0UlblnR+p2IJ2hR3Nkemu8rnBiKH3y39o/rGkEJ6w==
   dependencies:
     "@0x/subproviders" "^6.0.0"
     "@compound-finance/sol-coverage" "^4.0.0-r1"
@@ -4367,7 +4379,7 @@ ethereumjs-abi@0.6.7:
     bn.js "^4.11.8"
     ethereumjs-util "^6.0.0"
 
-ethereumjs-account@3.0.0, ethereumjs-account@^3.0.0:
+ethereumjs-account@3.0.0:
   version "3.0.0"
   resolved "https://registry.yarnpkg.com/ethereumjs-account/-/ethereumjs-account-3.0.0.tgz#728f060c8e0c6e87f1e987f751d3da25422570a9"
   integrity sha512-WP6BdscjiiPkQfF9PVfMcwx/rDvfZTjFKY0Uwc09zSQr9JfIVH87dYIJu0gNhBhpmovV4yq295fdllS925fnBA==
@@ -4407,7 +4419,7 @@ ethereumjs-block@^1.2.2, ethereumjs-block@^1.4.1, ethereumjs-block@^1.6.0:
     ethereumjs-util "^5.0.0"
     merkle-patricia-tree "^2.1.2"
 
-ethereumjs-block@~2.2.0, ethereumjs-block@~2.2.1:
+ethereumjs-block@~2.2.0:
   version "2.2.1"
   resolved "https://registry.yarnpkg.com/ethereumjs-block/-/ethereumjs-block-2.2.1.tgz#5fba423305b40ab6486a6b81922e5312b2667c8d"
   integrity sha512-ze8I1844m5oKZL7hiHuezRcPzqdi4Iv0ssqQyuRaJ9Je0/YCYfXobJHvNLnex2ETgs5JypicdtLYrCNWdgcLvg==
@@ -4434,22 +4446,6 @@ ethereumjs-blockchain@^3.4.0:
     safe-buffer "^5.1.2"
     semaphore "^1.1.0"
 
-ethereumjs-blockchain@^4.0.1:
-  version "4.0.2"
-  resolved "https://registry.yarnpkg.com/ethereumjs-blockchain/-/ethereumjs-blockchain-4.0.2.tgz#660c20df5895a88cec858738f286ec28d9a9acf6"
-  integrity sha512-K7N7EJpDQJXX634uEuXRk3pIH058SPeu+g0xQslViQyaTpJNTHsN5Wu/MdA5BzrUriBRlfmX9lCEaU4ZuaftJA==
-  dependencies:
-    async "^2.6.1"
-    ethashjs "~0.0.7"
-    ethereumjs-block "~2.2.1"
-    ethereumjs-common "^1.1.0"
-    ethereumjs-util "~6.1.0"
-    flow-stoplight "^1.0.0"
-    level-mem "^3.0.1"
-    lru-cache "^5.1.1"
-    rlp "^2.2.2"
-    semaphore "^1.1.0"
-
 ethereumjs-common@^1.1.0, ethereumjs-common@^1.3.1, ethereumjs-common@^1.3.2:
   version "1.4.0"
   resolved "https://registry.yarnpkg.com/ethereumjs-common/-/ethereumjs-common-1.4.0.tgz#a940685f88f3c2587e4061630fe720b089c965b8"
@@ -4471,7 +4467,7 @@ ethereumjs-tx@^2.1.1:
     ethereumjs-common "^1.3.1"
     ethereumjs-util "^6.0.0"
 
-ethereumjs-util@6.1.0, ethereumjs-util@~6.1.0:
+ethereumjs-util@6.1.0:
   version "6.1.0"
   resolved "https://registry.yarnpkg.com/ethereumjs-util/-/ethereumjs-util-6.1.0.tgz#e9c51e5549e8ebd757a339cc00f5380507e799c8"
   integrity sha512-URESKMFbDeJxnAxPppnk2fN6Y3BIatn9fwn76Lm8bQlt+s52TpG8dN9M66MLPuRAiAOIqL3dfwqWJf0sd0fL0Q==
@@ -4508,7 +4504,7 @@ ethereumjs-util@^5.0.0, ethereumjs-util@^5.0.1, ethereumjs-util@^5.1.1, ethereum
     safe-buffer "^5.1.1"
     secp256k1 "^3.0.1"
 
-ethereumjs-util@^6.0.0, ethereumjs-util@^6.1.0:
+ethereumjs-util@^6.0.0:
   version "6.2.0"
   resolved "https://registry.yarnpkg.com/ethereumjs-util/-/ethereumjs-util-6.2.0.tgz#23ec79b2488a7d041242f01e25f24e5ad0357960"
   integrity sha512-vb0XN9J2QGdZGIEKG2vXM+kUdEivUfU6Wmi5y0cg+LRhDYKnXIZ/Lz7XjFbHRR9VIKq2lVGLzGBkA++y2nOdOQ==
@@ -4552,27 +4548,6 @@ ethereumjs-vm@3.0.0:
     rustbn.js "~0.2.0"
     safe-buffer "^5.1.1"
 
-ethereumjs-vm@4.1.0:
-  version "4.1.0"
-  resolved "https://registry.yarnpkg.com/ethereumjs-vm/-/ethereumjs-vm-4.1.0.tgz#359ed3592636390a5b2909a28d955c908830daa5"
-  integrity sha512-qvgmKkyF+eZ6NvtqTV74z9oRB7UxUStA0gShEbXftovpukVIYVzhvCl9KvUi64Rpo8jufze6Z0zHhiQpZN0Izw==
-  dependencies:
-    async "^2.1.2"
-    async-eventemitter "^0.2.2"
-    core-js-pure "^3.0.1"
-    ethereumjs-account "^3.0.0"
-    ethereumjs-block "~2.2.0"
-    ethereumjs-blockchain "^4.0.1"
-    ethereumjs-common "^1.3.2"
-    ethereumjs-tx "^2.1.1"
-    ethereumjs-util "^6.1.0"
-    fake-merkle-patricia-tree "^1.0.1"
-    functional-red-black-tree "^1.0.1"
-    merkle-patricia-tree "^2.3.2"
-    rustbn.js "~0.2.0"
-    safe-buffer "^5.1.1"
-    util.promisify "^1.0.0"
-
 ethereumjs-vm@^2.1.0, ethereumjs-vm@^2.3.4, ethereumjs-vm@^2.6.0:
   version "2.6.0"
   resolved "https://registry.yarnpkg.com/ethereumjs-vm/-/ethereumjs-vm-2.6.0.tgz#76243ed8de031b408793ac33907fb3407fe400c6"
@@ -5251,43 +5226,19 @@ functional-red-black-tree@^1.0.1, functional-red-black-tree@~1.0.1:
   resolved "https://registry.yarnpkg.com/functional-red-black-tree/-/functional-red-black-tree-1.0.1.tgz#1b0ab3bd553b2a0d6399d29c0e3ea0b252078327"
   integrity sha1-GwqzvVU7Kg1jmdKcDj6gslIHgyc=
 
-ganache-core@^2.6.0:
-  version "2.8.0"
-  resolved "https://registry.yarnpkg.com/ganache-core/-/ganache-core-2.8.0.tgz#eeadc7f7fc3a0c20d99f8f62021fb80b5a05490c"
-  integrity sha512-hfXqZGJx700jJqwDHNXrU2BnPYuETn1ekm36oRHuXY3oOuJLFs5C+cFdUFaBlgUxcau1dOgZUUwKqTAy0gTA9Q==
+ganache-cli@^6.7.0:
+  version "6.7.0"
+  resolved "https://registry.yarnpkg.com/ganache-cli/-/ganache-cli-6.7.0.tgz#b59845578221bdf686cf124d007c5ee62e85a62f"
+  integrity sha512-9CZsClo9hl5MxGL7hkk14mie89Q94P0idh92jcV7LmppTYTCG7SHatuwcfqN7emFHArMt3fneN4QbH2do2N6Ow==
   dependencies:
-    abstract-leveldown "3.0.0"
-    async "2.6.2"
-    bip39 "2.5.0"
-    cachedown "1.0.0"
-    clone "2.1.2"
-    debug "3.2.6"
-    encoding-down "5.0.4"
-    eth-sig-util "2.3.0"
-    ethereumjs-abi "0.6.7"
-    ethereumjs-account "3.0.0"
-    ethereumjs-block "2.2.0"
-    ethereumjs-tx "1.3.7"
     ethereumjs-util "6.1.0"
-    ethereumjs-vm "3.0.0"
-    heap "0.2.6"
-    level-sublevel "6.6.4"
-    levelup "3.1.1"
-    lodash "4.17.14"
-    merkle-patricia-tree "2.3.2"
-    seedrandom "3.0.1"
     source-map-support "0.5.12"
-    tmp "0.1.0"
-    web3-provider-engine "14.2.1"
-    websocket "1.0.29"
-  optionalDependencies:
-    ethereumjs-wallet "0.6.3"
-    web3 "1.2.1"
+    yargs "13.2.4"
 
-ganache-core@^2.9.0-istanbul.0:
-  version "2.9.0-istanbul.0"
-  resolved "https://registry.yarnpkg.com/ganache-core/-/ganache-core-2.9.0-istanbul.0.tgz#bc336c770775a2b9fb06f5cae827088ecc194283"
-  integrity sha512-wqNWyxrfZe4QPxzaR/n4hGxIfa1iZAkymPg17wET0iWZ9uurMywGgpG4ZvxjVU9q7WCjIobOSzE1m9OT0dIYcQ==
+ganache-core@^2.6.0, ganache-core@^2.8.0:
+  version "2.8.0"
+  resolved "https://registry.yarnpkg.com/ganache-core/-/ganache-core-2.8.0.tgz#eeadc7f7fc3a0c20d99f8f62021fb80b5a05490c"
+  integrity sha512-hfXqZGJx700jJqwDHNXrU2BnPYuETn1ekm36oRHuXY3oOuJLFs5C+cFdUFaBlgUxcau1dOgZUUwKqTAy0gTA9Q==
   dependencies:
     abstract-leveldown "3.0.0"
     async "2.6.2"
@@ -5302,7 +5253,7 @@ ganache-core@^2.9.0-istanbul.0:
     ethereumjs-block "2.2.0"
     ethereumjs-tx "1.3.7"
     ethereumjs-util "6.1.0"
-    ethereumjs-vm "4.1.0"
+    ethereumjs-vm "3.0.0"
     heap "0.2.6"
     level-sublevel "6.6.4"
     levelup "3.1.1"
@@ -6014,6 +5965,11 @@ invert-kv@^1.0.0:
   resolved "https://registry.yarnpkg.com/invert-kv/-/invert-kv-1.0.0.tgz#104a8e4aaca6d3d8cd157a8ef8bfab2d7a3ffdb6"
   integrity sha1-EEqOSqym09jNFXqO+L+rLXo//bY=
 
+invert-kv@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/invert-kv/-/invert-kv-2.0.0.tgz#7393f5afa59ec9ff5f67a27620d11c226e3eec02"
+  integrity sha512-wPVv/y/QQ/Uiirj/vh3oP+1Ww+AWehmi1g5fFWGPF6IpCBCDVrhgHRMvrLfdYcwDh3QJbGXDW4JAuzxElLSqKA==
+
 ipaddr.js@1.9.0:
   version "1.9.0"
   resolved "https://registry.yarnpkg.com/ipaddr.js/-/ipaddr.js-1.9.0.tgz#37df74e430a0e47550fe54a2defe30d8acd95f65"
@@ -7229,6 +7185,13 @@ lcid@^1.0.0:
   dependencies:
     invert-kv "^1.0.0"
 
+lcid@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/lcid/-/lcid-2.0.0.tgz#6ef5d2df60e52f82eb228a4c373e8d1f397253cf"
+  integrity sha512-avPEb8P8EGnwXKClwsNUgryVjllcRqtMYa49NTsbQagYuT1DcXnl1915oxWjoyGrXR6zH/Y0Zc96xWsPcoDKeA==
+  dependencies:
+    invert-kv "^2.0.0"
+
 lead@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/lead/-/lead-1.0.0.tgz#6f14f99a37be3a9dd784f5495690e5903466ee42"
@@ -7560,6 +7523,13 @@ makeerror@1.0.x:
   dependencies:
     tmpl "1.0.x"
 
+map-age-cleaner@^0.1.1:
+  version "0.1.3"
+  resolved "https://registry.yarnpkg.com/map-age-cleaner/-/map-age-cleaner-0.1.3.tgz#7d583a7306434c055fe474b0f45078e6e1b4b92a"
+  integrity sha512-bJzx6nMoP6PDLPBFmg7+xRKeFZvFboMrGlxmNj9ClvX53KrmvM5bXFXEWjbz4cz1AFn+jWJ9z/DJSz7hrs0w3w==
+  dependencies:
+    p-defer "^1.0.0"
+
 map-cache@^0.2.0, map-cache@^0.2.2:
   version "0.2.2"
   resolved "https://registry.yarnpkg.com/map-cache/-/map-cache-0.2.2.tgz#c32abd0bd6525d9b051645bb4f26ac5dc98a0dbf"
@@ -7618,6 +7588,15 @@ mem@^1.1.0:
   dependencies:
     mimic-fn "^1.0.0"
 
+mem@^4.0.0:
+  version "4.3.0"
+  resolved "https://registry.yarnpkg.com/mem/-/mem-4.3.0.tgz#461af497bc4ae09608cdb2e60eefb69bff744178"
+  integrity sha512-qX2bG48pTqYRVmDB37rn/6PT7LcR8T7oAX3bf99u1Tt1nzxYfxkgqDwUwolPlXweM0XzBOBFzSx4kfp7KP1s/w==
+  dependencies:
+    map-age-cleaner "^0.1.1"
+    mimic-fn "^2.0.0"
+    p-is-promise "^2.0.0"
+
 memdown@^1.0.0:
   version "1.4.1"
   resolved "https://registry.yarnpkg.com/memdown/-/memdown-1.4.1.tgz#b4e4e192174664ffbae41361aa500f3119efe215"
@@ -7772,7 +7751,7 @@ mimic-fn@^1.0.0:
   resolved "https://registry.yarnpkg.com/mimic-fn/-/mimic-fn-1.2.0.tgz#820c86a39334640e99516928bd03fca88057d022"
   integrity sha512-jf84uxzwiuiIVKiOLpfYk7N46TSy8ubTonmneY9vrpHNAnp0QBt2BxWV9dO3/j+BoVAb+a5G6YDPW3M5HOdMWQ==
 
-mimic-fn@^2.1.0:
+mimic-fn@^2.0.0, mimic-fn@^2.1.0:
   version "2.1.0"
   resolved "https://registry.yarnpkg.com/mimic-fn/-/mimic-fn-2.1.0.tgz#7ed2c2ccccaf84d3ffcb7a69b57711fc2083401b"
   integrity sha512-OqbOk5oEQeAZ8WXWydlu9HJjz9WVdEIvamMCcXmuqUYjTknH/sqsWvhQ3vgwKFRR1HpjvNBKQ37nbJgYzGqGcg==
@@ -8261,12 +8240,12 @@ object.defaults@^1.0.0, object.defaults@^1.1.0:
     isobject "^3.0.0"
 
 object.getownpropertydescriptors@^2.0.3:
-  version "2.0.3"
-  resolved "https://registry.yarnpkg.com/object.getownpropertydescriptors/-/object.getownpropertydescriptors-2.0.3.tgz#8758c846f5b407adab0f236e0986f14b051caa16"
-  integrity sha1-h1jIRvW0B62rDyNuCYbxSwUcqhY=
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/object.getownpropertydescriptors/-/object.getownpropertydescriptors-2.1.0.tgz#369bf1f9592d8ab89d712dced5cb81c7c5352649"
+  integrity sha512-Z53Oah9A3TdLoblT7VKJaTDdXdT+lQO+cNpKVnya5JDe9uLvzu1YyY1yFDFrcxrlRgWrEFH0jJtD/IbuwjcEVg==
   dependencies:
-    define-properties "^1.1.2"
-    es-abstract "^1.5.1"
+    define-properties "^1.1.3"
+    es-abstract "^1.17.0-next.1"
 
 object.map@^1.0.0:
   version "1.0.1"
@@ -8375,6 +8354,15 @@ os-locale@^2.0.0:
     lcid "^1.0.0"
     mem "^1.1.0"
 
+os-locale@^3.1.0:
+  version "3.1.0"
+  resolved "https://registry.yarnpkg.com/os-locale/-/os-locale-3.1.0.tgz#a802a6ee17f24c10483ab9935719cef4ed16bf1a"
+  integrity sha512-Z8l3R4wYWM40/52Z+S265okfFj8Kt2cC2MKY+xNi3kFs+XGI7WXu/I309QQQYbRW4ijiZ+yxs9pqEhJh0DqW3Q==
+  dependencies:
+    execa "^1.0.0"
+    lcid "^2.0.0"
+    mem "^4.0.0"
+
 os-tmpdir@^1.0.0, os-tmpdir@^1.0.1, os-tmpdir@~1.0.2:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/os-tmpdir/-/os-tmpdir-1.0.2.tgz#bbe67406c79aa85c5cfec766fe5734555dfa1274"
@@ -8398,6 +8386,11 @@ p-cancelable@^1.0.0:
   resolved "https://registry.yarnpkg.com/p-cancelable/-/p-cancelable-1.1.0.tgz#d078d15a3af409220c886f1d9a0ca2e441ab26cc"
   integrity sha512-s73XxOZ4zpt1edZYZzvhqFa6uvQc1vwUa0K0BdtIZgQMAJj9IbebH+JkgKZc9h+B05PKHLOTl4ajG1BmNrVZlw==
 
+p-defer@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/p-defer/-/p-defer-1.0.0.tgz#9f6eb182f6c9aa8cd743004a7d4f96b196b0fb0c"
+  integrity sha1-n26xgvbJqozXQwBKfU+WsZaw+ww=
+
 p-each-series@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/p-each-series/-/p-each-series-1.0.0.tgz#930f3d12dd1f50e7434457a22cd6f04ac6ad7f71"
@@ -8415,6 +8408,11 @@ p-finally@^2.0.0:
   resolved "https://registry.yarnpkg.com/p-finally/-/p-finally-2.0.1.tgz#bd6fcaa9c559a096b680806f4d657b3f0f240561"
   integrity sha512-vpm09aKwq6H9phqRQzecoDpD8TmVyGw70qmWlyq5onxY7tqyTTFVvxMykxQSQKILBSFlbXpypIw2T1Ml7+DDtw==
 
+p-is-promise@^2.0.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/p-is-promise/-/p-is-promise-2.1.0.tgz#918cebaea248a62cf7ffab8e3bca8c5f882fc42e"
+  integrity sha512-Y3W0wlRPK8ZMRbNq97l4M5otioeA5lm1z7bkNkxCka8HSPjR0xRWmpCmc9utiaLP9Jb1eD8BgeIxTW4AIF45Pg==
+
 p-limit@^1.1.0:
   version "1.3.0"
   resolved "https://registry.yarnpkg.com/p-limit/-/p-limit-1.3.0.tgz#b86bd5f0c25690911c7590fcbfc2010d54b3ccb8"
@@ -9496,7 +9494,14 @@ ripemd160@^2.0.0, ripemd160@^2.0.1:
     hash-base "^3.0.0"
     inherits "^2.0.1"
 
-rlp@^2.0.0, rlp@^2.2.1, rlp@^2.2.2, rlp@^2.2.3:
+rlp@^2.0.0:
+  version "2.2.1"
+  resolved "https://registry.yarnpkg.com/rlp/-/rlp-2.2.1.tgz#9cacf53ad2579163cc56fba64b1f4336f1f2fa46"
+  integrity sha512-nqB/qy+YjXdp/zj1CjCiDwfLMBPv/XFDol0ir/7O/+Ix90++rvi+QoK1CDJcn8JoqCu2WrPPeRucu4qyIDzALg==
+  dependencies:
+    safe-buffer "^5.1.1"
+
+rlp@^2.2.1, rlp@^2.2.3:
   version "2.2.4"
   resolved "https://registry.yarnpkg.com/rlp/-/rlp-2.2.4.tgz#d6b0e1659e9285fc509a5d169a9bd06f704951c1"
   integrity sha512-fdq2yYCWpAQBhwkZv+Z8o/Z4sPmYm1CUq6P7n6lVTOdb949CnqA0sndXal5C1NleSVSZm6q5F3iEbauyVln/iw==
@@ -11882,7 +11887,7 @@ yargs-parser@^10.0.0:
   dependencies:
     camelcase "^4.1.0"
 
-yargs-parser@^13.1.1:
+yargs-parser@^13.1.0, yargs-parser@^13.1.1:
   version "13.1.1"
   resolved "https://registry.yarnpkg.com/yargs-parser/-/yargs-parser-13.1.1.tgz#d26058532aa06d365fe091f6a1fc06b2f7e5eca0"
   integrity sha512-oVAVsHz6uFrg3XQheFII8ESO2ssAf9luWuAd6Wexsu4F3OtIW0o8IribPXYrD4WC24LWtPrJlGy87y5udK+dxQ==
@@ -11904,6 +11909,23 @@ yargs-parser@^8.1.0:
   dependencies:
     camelcase "^4.1.0"
 
+yargs@13.2.4:
+  version "13.2.4"
+  resolved "https://registry.yarnpkg.com/yargs/-/yargs-13.2.4.tgz#0b562b794016eb9651b98bd37acf364aa5d6dc83"
+  integrity sha512-HG/DWAJa1PAnHT9JAhNa8AbAv3FPaiLzioSjCcmuXXhP8MlpHO5vwls4g4j6n30Z74GVQj8Xa62dWVx1QCGklg==
+  dependencies:
+    cliui "^5.0.0"
+    find-up "^3.0.0"
+    get-caller-file "^2.0.1"
+    os-locale "^3.1.0"
+    require-directory "^2.1.1"
+    require-main-filename "^2.0.0"
+    set-blocking "^2.0.0"
+    string-width "^3.0.0"
+    which-module "^2.0.0"
+    y18n "^4.0.0"
+    yargs-parser "^13.1.0"
+
 yargs@^10.0.3:
   version "10.1.2"
   resolved "https://registry.yarnpkg.com/yargs/-/yargs-10.1.2.tgz#454d074c2b16a51a43e2fb7807e4f9de69ccb5c5"