diff --git a/src/main/java/seedu/address/logic/CommandLog.java b/src/main/java/seedu/address/logic/CommandLog.java
index adad4869faf..d9f7afbb0ba 100644
--- a/src/main/java/seedu/address/logic/CommandLog.java
+++ b/src/main/java/seedu/address/logic/CommandLog.java
@@ -5,20 +5,40 @@
 import seedu.address.logic.commands.Command;
 
 /**
- * Keeps track of Commands given by user
+ * Keeps track of Commands given by user using a stack
  */
 public class CommandLog {
     private Stack<Command> log = new Stack<>();
+    private Stack<String> inputLog = new Stack<>();
 
+    /**
+     * Adds a command to the stack
+     */
     public void add(Command command) {
         log.push(command);
     }
 
-    public Command undo() {
+    /**
+     * Pops most recent command at the top of the stack
+     * @return null if stack is empty
+     */
+    public Command getPreviousCommand() {
         return log.isEmpty() ? null : log.pop();
     }
 
-    public boolean hasLog() {
-        return !log.isEmpty();
+    /**
+     * Adds a user input to the stack
+     */
+    public void addinput(String input) {
+        inputLog.push(input);
     }
+
+    /**
+     * Returns most recent user input at the top of the stack
+     * @return empty string if stack is empty
+     */
+    public String getPreviousInput() {
+        return inputLog.isEmpty() ? "" : inputLog.pop();
+    }
+
 }
diff --git a/src/main/java/seedu/address/logic/LogicManager.java b/src/main/java/seedu/address/logic/LogicManager.java
index bb01951a735..59cc5ad3548 100644
--- a/src/main/java/seedu/address/logic/LogicManager.java
+++ b/src/main/java/seedu/address/logic/LogicManager.java
@@ -50,6 +50,11 @@ public CommandResult execute(String commandText) throws CommandException, ParseE
         CommandResult commandResult;
         Command command = addressBookParser.parseCommand(commandText);
         commandResult = command.execute(model);
+        if (command.canBeUndone()) {
+            model.addInputToLog(commandText);
+            model.addCommandToLog(command);
+        }
+
         if (commandResult.isLoad()) {
             try {
                 Optional<ReadOnlyAddressBook> loadedAddressBookOpt = storage.loadAddressBookManually();
diff --git a/src/main/java/seedu/address/logic/commands/AddCommand.java b/src/main/java/seedu/address/logic/commands/AddCommand.java
index 75c0818a551..4abac2a25a6 100644
--- a/src/main/java/seedu/address/logic/commands/AddCommand.java
+++ b/src/main/java/seedu/address/logic/commands/AddCommand.java
@@ -46,6 +46,7 @@ public class AddCommand extends Command {
 
     public static final String MESSAGE_SUCCESS = "New person added: %1$s";
     public static final String MESSAGE_DUPLICATE_PERSON = "This person already exists in the address book";
+    private static final boolean IS_UNDOABLE = true;
 
     private final Person toAdd;
     private Predicate<Person> previousPredicate;
@@ -68,7 +69,6 @@ public CommandResult execute(Model model) throws CommandException {
 
         previousPredicate = model.getCurrentPredicate();
         model.addPerson(toAdd);
-        model.addCommandToLog(this);
         return new CommandResult(String.format(MESSAGE_SUCCESS, Messages.format(toAdd)));
     }
 
@@ -82,6 +82,11 @@ public void undo(Model model) {
         model.updateFilteredPersonList(previousPredicate);
     }
 
+    @Override
+    public boolean canBeUndone() {
+        return IS_UNDOABLE;
+    }
+
     @Override
     public boolean equals(Object other) {
         if (other == this) {
diff --git a/src/main/java/seedu/address/logic/commands/AddGameCommand.java b/src/main/java/seedu/address/logic/commands/AddGameCommand.java
index 3e44ac59ddf..5362e44ba03 100644
--- a/src/main/java/seedu/address/logic/commands/AddGameCommand.java
+++ b/src/main/java/seedu/address/logic/commands/AddGameCommand.java
@@ -44,6 +44,7 @@ public class AddGameCommand extends Command {
 
     public static final String MESSAGE_ADD_GAME_SUCCESS = "Added Game to Person: %1$s";
     public static final String MESSAGE_GAME_EXISTS = "The game provided already exists for that person.";
+    private static final boolean IS_UNDOABLE = true;
 
     private final Index index;
     private final GameDescriptor addGameDescriptor;
@@ -90,7 +91,6 @@ public CommandResult execute(Model model) throws CommandException {
         }
         gameMap.put(gameName, editedGame);
         model.setPerson(personToEdit, personToEdit);
-        model.addCommandToLog(this);
         return new CommandResult(String.format(MESSAGE_ADD_GAME_SUCCESS, Messages.format(editedGame)));
     }
 
@@ -104,6 +104,11 @@ public void undo(Model model) {
         model.setPerson(personToEdit, personToEdit);
     }
 
+    @Override
+    public boolean canBeUndone() {
+        return IS_UNDOABLE;
+    }
+
     /**
      * Creates and returns a {@code Game} with the details of {@code addGameDescriptor}
      */
diff --git a/src/main/java/seedu/address/logic/commands/ClearCommand.java b/src/main/java/seedu/address/logic/commands/ClearCommand.java
index b4aea30098b..0302f3cf8df 100644
--- a/src/main/java/seedu/address/logic/commands/ClearCommand.java
+++ b/src/main/java/seedu/address/logic/commands/ClearCommand.java
@@ -13,6 +13,7 @@ public class ClearCommand extends Command {
 
     public static final String COMMAND_WORD = "clear";
     public static final String MESSAGE_SUCCESS = "Address book has been cleared!";
+    private static final boolean IS_UNDOABLE = true;
 
     private ReadOnlyAddressBook previousAddressBook;
 
@@ -22,7 +23,6 @@ public CommandResult execute(Model model) {
         requireNonNull(model);
         previousAddressBook = new AddressBook(model.getAddressBook());
         model.setAddressBook(new AddressBook());
-        model.addCommandToLog(this);
         return new CommandResult(MESSAGE_SUCCESS);
     }
 
@@ -30,4 +30,9 @@ public CommandResult execute(Model model) {
     public void undo(Model model) {
         model.setAddressBook(previousAddressBook);
     }
+
+    @Override
+    public boolean canBeUndone() {
+        return IS_UNDOABLE;
+    }
 }
diff --git a/src/main/java/seedu/address/logic/commands/Command.java b/src/main/java/seedu/address/logic/commands/Command.java
index 529f93dabbc..3b89b0df340 100644
--- a/src/main/java/seedu/address/logic/commands/Command.java
+++ b/src/main/java/seedu/address/logic/commands/Command.java
@@ -22,4 +22,8 @@ public abstract class Command {
      */
     public abstract void undo(Model model);
 
+    /**
+     * Returns whether the command can be undone.
+     */
+    public abstract boolean canBeUndone();
 }
diff --git a/src/main/java/seedu/address/logic/commands/DeleteCommand.java b/src/main/java/seedu/address/logic/commands/DeleteCommand.java
index ecc2bffe85a..d0efb3ebbb4 100644
--- a/src/main/java/seedu/address/logic/commands/DeleteCommand.java
+++ b/src/main/java/seedu/address/logic/commands/DeleteCommand.java
@@ -24,6 +24,7 @@ public class DeleteCommand extends Command {
             + "Example: " + COMMAND_WORD + " 1";
 
     public static final String MESSAGE_DELETE_PERSON_SUCCESS = "Deleted Person: %1$s";
+    private static final boolean IS_UNDOABLE = true;
 
     private final Index targetIndex;
 
@@ -48,7 +49,6 @@ public CommandResult execute(Model model) throws CommandException {
                 model.getAddressBookIndex(targetIndex.getZeroBased()));
         model.deletePerson(personToDelete);
         deletedPerson = personToDelete;
-        model.addCommandToLog(this);
         return new CommandResult(String.format(MESSAGE_DELETE_PERSON_SUCCESS, Messages.format(personToDelete)));
     }
 
@@ -60,6 +60,11 @@ public void undo(Model model) {
         model.insertPerson(deletedPerson, deletedPersonIndex.getZeroBased());
     }
 
+    @Override
+    public boolean canBeUndone() {
+        return IS_UNDOABLE;
+    }
+
     @Override
     public boolean equals(Object other) {
         if (other == this) {
diff --git a/src/main/java/seedu/address/logic/commands/DeleteGameCommand.java b/src/main/java/seedu/address/logic/commands/DeleteGameCommand.java
index a7c71b3169d..22b048bf51f 100644
--- a/src/main/java/seedu/address/logic/commands/DeleteGameCommand.java
+++ b/src/main/java/seedu/address/logic/commands/DeleteGameCommand.java
@@ -31,6 +31,7 @@ public class DeleteGameCommand extends Command {
 
     public static final String MESSAGE_DELETE_GAME_SUCCESS = "Deleted Game from Person: %1$s";
     public static final String MESSAGE_NOT_DELETED = "The game provided does not exist for that person.";
+    private static final boolean IS_UNDOABLE = true;
 
     private final Index index;
     private final String gameName;
@@ -69,7 +70,6 @@ public CommandResult execute(Model model) throws CommandException {
 
         deletedGame = gameMap.remove(gameName);
         model.setPerson(personToEdit, personToEdit);
-        model.addCommandToLog(this);
         return new CommandResult(String.format(MESSAGE_DELETE_GAME_SUCCESS, Messages.format(deletedGame)));
     }
 
@@ -83,6 +83,10 @@ public void undo(Model model) {
         model.setPerson(personToEdit, personToEdit);
     }
 
+    @Override
+    public boolean canBeUndone() {
+        return IS_UNDOABLE;
+    }
 
     @Override
     public boolean equals(Object other) {
diff --git a/src/main/java/seedu/address/logic/commands/EditCommand.java b/src/main/java/seedu/address/logic/commands/EditCommand.java
index b31e6fcb1ed..f8546675e13 100644
--- a/src/main/java/seedu/address/logic/commands/EditCommand.java
+++ b/src/main/java/seedu/address/logic/commands/EditCommand.java
@@ -8,7 +8,6 @@
 import static seedu.address.logic.parser.CliSyntax.PREFIX_PHONE;
 import static seedu.address.logic.parser.CliSyntax.PREFIX_PREFERREDTIME;
 import static seedu.address.logic.parser.CliSyntax.PREFIX_TAG;
-import static seedu.address.model.Model.PREDICATE_SHOW_ALL_PERSONS;
 
 import java.util.Collections;
 import java.util.HashMap;
@@ -59,6 +58,7 @@ public class EditCommand extends Command {
     public static final String MESSAGE_EDIT_PERSON_SUCCESS = "Edited Person: %1$s";
     public static final String MESSAGE_NOT_EDITED = "At least one field to edit must be provided.";
     public static final String MESSAGE_DUPLICATE_PERSON = "This person already exists in the address book.";
+    private static final boolean IS_UNDOABLE = true;
 
     private final Index index;
     private final EditPersonDescriptor editPersonDescriptor;
@@ -94,8 +94,6 @@ public CommandResult execute(Model model) throws CommandException {
         }
 
         model.setPerson(personToEdit, editedPerson);
-        model.updateFilteredPersonList(PREDICATE_SHOW_ALL_PERSONS);
-        model.addCommandToLog(this);
         return new CommandResult(String.format(MESSAGE_EDIT_PERSON_SUCCESS, Messages.format(editedPerson)));
     }
 
@@ -104,7 +102,11 @@ public void undo(Model model) {
         requireNonNull(model);
 
         model.setPerson(editedPerson, personToEdit);
-        model.updateFilteredPersonList(PREDICATE_SHOW_ALL_PERSONS);
+    }
+
+    @Override
+    public boolean canBeUndone() {
+        return IS_UNDOABLE;
     }
 
     /**
diff --git a/src/main/java/seedu/address/logic/commands/EditGameCommand.java b/src/main/java/seedu/address/logic/commands/EditGameCommand.java
index c6de5e9f636..c1e531e7ad5 100644
--- a/src/main/java/seedu/address/logic/commands/EditGameCommand.java
+++ b/src/main/java/seedu/address/logic/commands/EditGameCommand.java
@@ -44,6 +44,7 @@ public class EditGameCommand extends Command {
 
     public static final String MESSAGE_EDIT_GAME_SUCCESS = "Edited Game: %1$s";
     public static final String MESSAGE_NOT_EDITED = "At least one field to edit must be provided.";
+    private static final boolean IS_UNDOABLE = true;
 
     private final Index index;
     private final String gameName;
@@ -86,7 +87,6 @@ public CommandResult execute(Model model) throws CommandException {
         Game editedGame = createEditedGame(gameToEdit, editGameDescriptor);
         gameMap.put(gameName, editedGame);
         model.setPerson(personToEdit, personToEdit);
-        model.addCommandToLog(this);
         return new CommandResult(String.format(MESSAGE_EDIT_GAME_SUCCESS, Messages.format(editedGame)));
     }
 
@@ -98,6 +98,11 @@ public void undo(Model model) {
         model.setPerson(personToEdit, personToEdit);
     }
 
+    @Override
+    public boolean canBeUndone() {
+        return IS_UNDOABLE;
+    }
+
     /**
      * Creates and returns a {@code Game} with the details of {@code gameToEdit}
      * edited with {@code editGameDescriptor}.
diff --git a/src/main/java/seedu/address/logic/commands/ExitCommand.java b/src/main/java/seedu/address/logic/commands/ExitCommand.java
index 981bf332e21..cc353e09bf7 100644
--- a/src/main/java/seedu/address/logic/commands/ExitCommand.java
+++ b/src/main/java/seedu/address/logic/commands/ExitCommand.java
@@ -10,6 +10,7 @@ public class ExitCommand extends Command {
     public static final String COMMAND_WORD = "exit";
 
     public static final String MESSAGE_EXIT_ACKNOWLEDGEMENT = "Exiting Address Book as requested ...";
+    private static final boolean IS_UNDOABLE = false;
 
     @Override
     public CommandResult execute(Model model) {
@@ -21,4 +22,8 @@ public void undo(Model model) {
 
     }
 
+    @Override
+    public boolean canBeUndone() {
+        return IS_UNDOABLE;
+    }
 }
diff --git a/src/main/java/seedu/address/logic/commands/FavouriteGameCommand.java b/src/main/java/seedu/address/logic/commands/FavouriteGameCommand.java
index e440e9a21f5..a2eec17e942 100644
--- a/src/main/java/seedu/address/logic/commands/FavouriteGameCommand.java
+++ b/src/main/java/seedu/address/logic/commands/FavouriteGameCommand.java
@@ -30,6 +30,7 @@ public class FavouriteGameCommand extends Command {
     public static final String MESSAGE_FAVOURITE_GAME_SUCCESS = "Favourited Game: %1$s";
     public static final String MESSAGE_GAME_NOT_SPECIFIED = "Please specify a game!";
     public static final String MESSAGE_GAME_NOT_FOUND = "Game not found!";
+    private static final boolean IS_UNDOABLE = true;
 
     private Index index;
     private String gameName;
@@ -66,7 +67,6 @@ public CommandResult execute(Model model) throws CommandException {
         prevGameIsFavourite = targetGame.getFavouriteStatus();
         targetGame.setAsFavourite();
         model.setPerson(targetPerson, targetPerson);
-        model.addCommandToLog(this);
         return new CommandResult(String.format(MESSAGE_FAVOURITE_GAME_SUCCESS, gameName));
     }
 
@@ -90,6 +90,11 @@ public void undo(Model model) {
         model.setPerson(targetPerson, targetPerson);
     }
 
+    @Override
+    public boolean canBeUndone() {
+        return IS_UNDOABLE;
+    }
+
     @Override
     public boolean equals(Object other) {
         if (other == this) {
diff --git a/src/main/java/seedu/address/logic/commands/FindCommand.java b/src/main/java/seedu/address/logic/commands/FindCommand.java
index ec185ec6f9f..7acba5e4456 100644
--- a/src/main/java/seedu/address/logic/commands/FindCommand.java
+++ b/src/main/java/seedu/address/logic/commands/FindCommand.java
@@ -22,6 +22,7 @@ public class FindCommand extends Command {
             + "the specified keywords (case-insensitive) and displays them as a list with index numbers.\n"
             + "Parameters: KEYWORD [MORE_KEYWORDS]...\n"
             + "Example: " + COMMAND_WORD + " alice bob charlie";
+    private static final boolean IS_UNDOABLE = true;
 
     private final NameContainsKeywordsPredicate predicate;
     private Predicate<Person> previousPredicate;
@@ -35,7 +36,6 @@ public CommandResult execute(Model model) {
         requireNonNull(model);
         previousPredicate = model.getCurrentPredicate();
         model.updateFilteredPersonList(predicate);
-        model.addCommandToLog(this);
         return new CommandResult(
                 String.format(Messages.MESSAGE_PERSONS_LISTED_OVERVIEW, model.getFilteredPersonList().size()));
     }
@@ -46,6 +46,11 @@ public void undo(Model model) {
         model.updateFilteredPersonList(previousPredicate);
     }
 
+    @Override
+    public boolean canBeUndone() {
+        return IS_UNDOABLE;
+    }
+
     @Override
     public boolean equals(Object other) {
         if (other == this) {
diff --git a/src/main/java/seedu/address/logic/commands/FindTimeCommand.java b/src/main/java/seedu/address/logic/commands/FindTimeCommand.java
index b58528bf72c..899628cfe17 100644
--- a/src/main/java/seedu/address/logic/commands/FindTimeCommand.java
+++ b/src/main/java/seedu/address/logic/commands/FindTimeCommand.java
@@ -24,6 +24,7 @@ public class FindTimeCommand extends Command {
             + "Tips: RANGE has format HHmm, same ending time as starting time is allowed.\n"
             + "Parameters: RANGE [MORE_RANGES]...\n"
             + "Example: " + COMMAND_WORD + " 1100-1230 2130-2245";
+    private static final boolean IS_UNDOABLE = true;
 
     private final PreferredTimeOverlapsRangesPredicate predicate;
     private Predicate<Person> previousPredicate;
@@ -37,7 +38,6 @@ public CommandResult execute(Model model) {
         requireNonNull(model);
         previousPredicate = model.getCurrentPredicate();
         model.updateFilteredPersonList(predicate);
-        model.addCommandToLog(this);
         return new CommandResult(
                 String.format(Messages.MESSAGE_PERSONS_LISTED_OVERVIEW, model.getFilteredPersonList().size()));
     }
@@ -48,6 +48,11 @@ public void undo(Model model) {
         model.updateFilteredPersonList(previousPredicate);
     }
 
+    @Override
+    public boolean canBeUndone() {
+        return IS_UNDOABLE;
+    }
+
     @Override
     public boolean equals(Object other) {
         if (other == this) {
diff --git a/src/main/java/seedu/address/logic/commands/HelpCommand.java b/src/main/java/seedu/address/logic/commands/HelpCommand.java
index 139f70dba28..18c7743a4e2 100644
--- a/src/main/java/seedu/address/logic/commands/HelpCommand.java
+++ b/src/main/java/seedu/address/logic/commands/HelpCommand.java
@@ -13,6 +13,7 @@ public class HelpCommand extends Command {
             + "Example: " + COMMAND_WORD;
 
     public static final String SHOWING_HELP_MESSAGE = "Opened help window.";
+    private static final boolean IS_UNDOABLE = false;
 
     @Override
     public CommandResult execute(Model model) {
@@ -23,4 +24,9 @@ public CommandResult execute(Model model) {
     public void undo(Model model) {
 
     }
+
+    @Override
+    public boolean canBeUndone() {
+        return IS_UNDOABLE;
+    }
 }
diff --git a/src/main/java/seedu/address/logic/commands/ListCommand.java b/src/main/java/seedu/address/logic/commands/ListCommand.java
index be8cdc5d591..a33ed6befab 100644
--- a/src/main/java/seedu/address/logic/commands/ListCommand.java
+++ b/src/main/java/seedu/address/logic/commands/ListCommand.java
@@ -16,6 +16,7 @@ public class ListCommand extends Command {
     public static final String COMMAND_WORD = "list";
 
     public static final String MESSAGE_SUCCESS = "Listed all persons";
+    private static final boolean IS_UNDOABLE = true;
 
     private Predicate<Person> previousPredicate;
 
@@ -24,7 +25,6 @@ public CommandResult execute(Model model) {
         requireNonNull(model);
         previousPredicate = model.getCurrentPredicate();
         model.updateFilteredPersonList(PREDICATE_SHOW_ALL_PERSONS);
-        model.addCommandToLog(this);
         return new CommandResult(MESSAGE_SUCCESS);
     }
 
@@ -33,4 +33,9 @@ public void undo(Model model) {
         requireNonNull(model);
         model.updateFilteredPersonList(previousPredicate);
     }
+
+    @Override
+    public boolean canBeUndone() {
+        return IS_UNDOABLE;
+    }
 }
diff --git a/src/main/java/seedu/address/logic/commands/LoadCommand.java b/src/main/java/seedu/address/logic/commands/LoadCommand.java
index ed9d3a953f5..1da542e3ee2 100644
--- a/src/main/java/seedu/address/logic/commands/LoadCommand.java
+++ b/src/main/java/seedu/address/logic/commands/LoadCommand.java
@@ -8,6 +8,9 @@
 public class LoadCommand extends Command {
     public static final String COMMAND_WORD = "load";
     public static final String MESSAGE_SUCCESS = "The saved address book has been loaded!";
+    private static final boolean IS_UNDOABLE = false;
+
+    @Override
     public CommandResult execute(Model model) throws CommandException {
         return new CommandResult(MESSAGE_SUCCESS, false, false, false, true);
     }
@@ -16,4 +19,9 @@ public CommandResult execute(Model model) throws CommandException {
     public void undo(Model model) {
 
     }
+
+    @Override
+    public boolean canBeUndone() {
+        return IS_UNDOABLE;
+    }
 }
diff --git a/src/main/java/seedu/address/logic/commands/SaveCommand.java b/src/main/java/seedu/address/logic/commands/SaveCommand.java
index 60febbe2698..a541c09cab6 100644
--- a/src/main/java/seedu/address/logic/commands/SaveCommand.java
+++ b/src/main/java/seedu/address/logic/commands/SaveCommand.java
@@ -9,6 +9,9 @@
 public class SaveCommand extends Command {
     public static final String COMMAND_WORD = "save";
     public static final String MESSAGE_SUCCESS = "Address book has been saved!";
+    private static final boolean IS_UNDOABLE = false;
+
+    @Override
     public CommandResult execute(Model model) throws CommandException {
         return new CommandResult(MESSAGE_SUCCESS, false, false, true, false);
     }
@@ -17,4 +20,9 @@ public CommandResult execute(Model model) throws CommandException {
     public void undo(Model model) {
 
     }
+
+    @Override
+    public boolean canBeUndone() {
+        return IS_UNDOABLE;
+    }
 }
diff --git a/src/main/java/seedu/address/logic/commands/UndoCommand.java b/src/main/java/seedu/address/logic/commands/UndoCommand.java
index 8e326c47e34..ce445e03589 100644
--- a/src/main/java/seedu/address/logic/commands/UndoCommand.java
+++ b/src/main/java/seedu/address/logic/commands/UndoCommand.java
@@ -13,8 +13,10 @@ public class UndoCommand extends Command {
     public static final String MESSAGE_USAGE = COMMAND_WORD + ": Undoes previous user command.\n"
             + "Example: " + COMMAND_WORD;
 
-    public static final String MESSAGE_SUCCESS = "Undid previous command.";
+    //public static final String MESSAGE_SUCCESS = "Undid previous command.";
+    public static final String MESSAGE_SUCCESS = "Undid previous command: %1$s";
     public static final String MESSAGE_INVALID_PREVIOUS_COMMAND = "No Command found to undo";
+    private static final boolean IS_UNDOABLE = false;
 
     @Override
     public CommandResult execute(Model model) throws CommandException {
@@ -23,11 +25,16 @@ public CommandResult execute(Model model) throws CommandException {
             throw new CommandException(MESSAGE_INVALID_PREVIOUS_COMMAND);
         }
         previousCommand.undo(model);
-        return new CommandResult(MESSAGE_SUCCESS);
+        return new CommandResult(String.format(MESSAGE_SUCCESS, model.getPreviousInput()));
     }
 
     @Override
     public void undo(Model model) {
 
     }
+
+    @Override
+    public boolean canBeUndone() {
+        return IS_UNDOABLE;
+    }
 }
diff --git a/src/main/java/seedu/address/logic/commands/UnfavouriteGameCommand.java b/src/main/java/seedu/address/logic/commands/UnfavouriteGameCommand.java
index f5baa5859c0..b02f3d8d0cf 100644
--- a/src/main/java/seedu/address/logic/commands/UnfavouriteGameCommand.java
+++ b/src/main/java/seedu/address/logic/commands/UnfavouriteGameCommand.java
@@ -31,6 +31,7 @@ public class UnfavouriteGameCommand extends Command {
     public static final String MESSAGE_UNFAVOURITE_GAME_SUCCESS = "Un-favourited Game: %1$s";
     public static final String MESSAGE_GAME_NOT_SPECIFIED = "Please specify a game!";
     public static final String MESSAGE_GAME_NOT_FOUND = "Game not found!";
+    private static final boolean IS_UNDOABLE = true;
 
     private Index index;
     private String gameName;
@@ -67,7 +68,6 @@ public CommandResult execute(Model model) throws CommandException {
         prevGameIsFavourite = targetGame.getFavouriteStatus();
         targetGame.removeFavourite();
         model.setPerson(targetPerson, targetPerson);
-        model.addCommandToLog(this);
         return new CommandResult(String.format(MESSAGE_UNFAVOURITE_GAME_SUCCESS, gameName));
     }
 
@@ -91,6 +91,11 @@ public void undo(Model model) {
         model.setPerson(targetPerson, targetPerson);
     }
 
+    @Override
+    public boolean canBeUndone() {
+        return IS_UNDOABLE;
+    }
+
     @Override
     public boolean equals(Object other) {
         if (other == this) {
diff --git a/src/main/java/seedu/address/model/Model.java b/src/main/java/seedu/address/model/Model.java
index 66eea9a0ba2..4b362e97031 100644
--- a/src/main/java/seedu/address/model/Model.java
+++ b/src/main/java/seedu/address/model/Model.java
@@ -107,7 +107,18 @@ public interface Model {
     void addCommandToLog(Command command);
 
     /**
-     * Returns most recent {@code Command} in {@code CommandLog}.
+     * Returns and removes most recent {@code Command} in {@code CommandLog}.
      */
     Command getPreviousCommand();
+
+    /**
+     * Adds the user input string to {@code CommandLog}.
+     */
+    void addInputToLog(String input);
+
+    /**
+     * Returns and removes most recent user input string in {@code CommandLog}.
+     * @return
+     */
+    String getPreviousInput();
 }
diff --git a/src/main/java/seedu/address/model/ModelManager.java b/src/main/java/seedu/address/model/ModelManager.java
index d65783c92ed..cf7ee155741 100644
--- a/src/main/java/seedu/address/model/ModelManager.java
+++ b/src/main/java/seedu/address/model/ModelManager.java
@@ -177,7 +177,16 @@ public void addCommandToLog(Command command) {
 
     @Override
     public Command getPreviousCommand() {
-        return commandLog.undo();
+        return commandLog.getPreviousCommand();
     }
 
+    @Override
+    public void addInputToLog(String input) {
+        commandLog.addinput(input);
+    }
+
+    @Override
+    public String getPreviousInput() {
+        return commandLog.getPreviousInput();
+    }
 }
diff --git a/src/main/java/seedu/address/ui/HelpWindow.java b/src/main/java/seedu/address/ui/HelpWindow.java
index 8165596d46b..82bba826958 100644
--- a/src/main/java/seedu/address/ui/HelpWindow.java
+++ b/src/main/java/seedu/address/ui/HelpWindow.java
@@ -74,8 +74,6 @@ public String getDescription() {
      */
     public HelpWindow(Stage root) {
         super(FXML, root);
-
-        this.getRoot().setResizable(true);
         this.getRoot().setMinHeight(500);
         this.getRoot().setMinWidth(600);
 
diff --git a/src/test/java/seedu/address/logic/commands/AddCommandTest.java b/src/test/java/seedu/address/logic/commands/AddCommandTest.java
index 8dd7722ab75..6227d15a01c 100644
--- a/src/test/java/seedu/address/logic/commands/AddCommandTest.java
+++ b/src/test/java/seedu/address/logic/commands/AddCommandTest.java
@@ -182,6 +182,16 @@ public void addCommandToLog(Command command) {
         public Command getPreviousCommand() {
             throw new AssertionError("This method should not be called.");
         }
+
+        @Override
+        public void addInputToLog(String input) {
+            throw new AssertionError("This method should not be called.");
+        }
+
+        @Override
+        public String getPreviousInput() {
+            throw new AssertionError("This method should not be called.");
+        }
     }
 
     /**
@@ -234,6 +244,10 @@ public Predicate<Person> getCurrentPredicate() {
         public ReadOnlyAddressBook getAddressBook() {
             return new AddressBook();
         }
-    }
 
+        @Override
+        public void addInputToLog(String input) {
+
+        }
+    }
 }
diff --git a/src/test/java/seedu/address/logic/commands/CommandTestUtil.java b/src/test/java/seedu/address/logic/commands/CommandTestUtil.java
index 82b1816bfc4..ca2f8a93426 100644
--- a/src/test/java/seedu/address/logic/commands/CommandTestUtil.java
+++ b/src/test/java/seedu/address/logic/commands/CommandTestUtil.java
@@ -108,6 +108,24 @@ public static void assertCommandSuccess(Command command, Model actualModel, Stri
         assertCommandSuccess(command, actualModel, expectedCommandResult, expectedModel);
     }
 
+    /**
+     * Executes the given {@code command} while unfiltering the {@code actualModel}, confirms that <br>
+     * - the returned {@link CommandResult} matches {@code expectedMessage} <br>
+     * - the {@code actualModel} matches {@code expectedModel}
+     */
+    public static void assertCommandSuccessUnfilter(Command command, Model actualModel, String expectedMessage,
+                                            Model expectedModel) {
+        CommandResult expectedCommandResult = new CommandResult(expectedMessage);
+        try {
+            CommandResult result = command.execute(actualModel);
+            actualModel.updateFilteredPersonList(unused -> true);
+            assertEquals(expectedCommandResult, result);
+            assertEquals(expectedModel, actualModel);
+        } catch (CommandException ce) {
+            throw new AssertionError("Execution of command should not fail.", ce);
+        }
+    }
+
     /**
      * Executes the given {@code command}, confirms that <br>
      * - a {@code CommandException} is thrown <br>
diff --git a/src/test/java/seedu/address/logic/commands/EditCommandTest.java b/src/test/java/seedu/address/logic/commands/EditCommandTest.java
index 469dd97daa7..d2629ca2741 100644
--- a/src/test/java/seedu/address/logic/commands/EditCommandTest.java
+++ b/src/test/java/seedu/address/logic/commands/EditCommandTest.java
@@ -10,6 +10,7 @@
 import static seedu.address.logic.commands.CommandTestUtil.VALID_TAG_HUSBAND;
 import static seedu.address.logic.commands.CommandTestUtil.assertCommandFailure;
 import static seedu.address.logic.commands.CommandTestUtil.assertCommandSuccess;
+import static seedu.address.logic.commands.CommandTestUtil.assertCommandSuccessUnfilter;
 import static seedu.address.logic.commands.CommandTestUtil.showPersonAtIndex;
 import static seedu.address.testutil.TypicalIndexes.INDEX_FIRST_PERSON;
 import static seedu.address.testutil.TypicalIndexes.INDEX_SECOND_PERSON;
@@ -95,8 +96,7 @@ public void execute_filteredList_success() {
 
         Model expectedModel = new ModelManager(new AddressBook(model.getAddressBook()), new UserPrefs());
         expectedModel.setPerson(model.getFilteredPersonList().get(0), editedPerson);
-
-        assertCommandSuccess(editCommand, model, expectedMessage, expectedModel);
+        assertCommandSuccessUnfilter(editCommand, model, expectedMessage, expectedModel);
     }
 
     @Test
diff --git a/src/test/java/seedu/address/logic/commands/EditGameCommandTest.java b/src/test/java/seedu/address/logic/commands/EditGameCommandTest.java
index 7a41d18ad10..14fd6b5e413 100644
--- a/src/test/java/seedu/address/logic/commands/EditGameCommandTest.java
+++ b/src/test/java/seedu/address/logic/commands/EditGameCommandTest.java
@@ -3,6 +3,7 @@
 import static org.junit.jupiter.api.Assertions.assertTrue;
 import static seedu.address.logic.commands.CommandTestUtil.assertCommandFailure;
 import static seedu.address.logic.commands.CommandTestUtil.assertCommandSuccess;
+import static seedu.address.logic.commands.CommandTestUtil.assertCommandSuccessUnfilter;
 import static seedu.address.logic.commands.CommandTestUtil.showPersonAtIndex;
 import static seedu.address.testutil.TypicalIndexes.INDEX_FIRST_PERSON;
 import static seedu.address.testutil.TypicalIndexes.INDEX_SECOND_PERSON;
@@ -112,8 +113,7 @@ public void execute_filteredList_success() {
 
         Model expectedModel = new ModelManager(new AddressBook(model.getAddressBook()), new UserPrefs());
         expectedModel.setPerson(model.getFilteredPersonList().get(0), editedPerson);
-        showPersonAtIndex(expectedModel, INDEX_FIRST_PERSON);
-        assertCommandSuccess(editCommand, model, expectedMessage, expectedModel);
+        assertCommandSuccessUnfilter(editCommand, model, expectedMessage, expectedModel);
     }
 
     @Test