After reading The Black Hack, reviews of Whitehack, and Sharp Swords and Sinister Spells (yet another "Hack" system hack)...
Roll 3d6 for a series of stats, such as: STR(ength), DEX(terity), END(urance), INT(elligence), POW(er), PRE(sence)
- Set HPs (Hit Points) from the average of STR & END
- MPs from POW
In most cases, your character rolls equal or less than a stat on D20 to succeed in some effort they might reasonably attempt under pressure, given their background and inclinations. Modifiers apply to shift the stat target. A "1" always succeeds and usually grants a critical result.
Magic-using types might select two or three spell options (see Hack Magic), but lack battle experience.
When characters advance, they get a chance to raise their stats. Maybe another chance to raise a favoured stat.
Generally, roll against STR to hack at things, and DEX to avoid being hacked, or shoot something.
- Use 1d6 for lighter or improvised weapons, 1d8 for martial weapons, when you roll for damage to HP.
- Deduct Armour Reduction (AR), 1-5 (leather, gambeson, maille, half-plate, plate), from any damage you take.
Only a character with battle experience can attack and avoid in the same round (so green fighters have to choose to attack or dodge).
Creatures get HP (the GM rolls a number of dice) and Ranks that apply to rolls in combat:
- Threat Rank (TR) modifies STR and DEX
- Power Rank (PR) modifies INT or POW (for spells and other eerie stuff)
Spell casters burn MPs to launch magic. They roll against INT or POW when under pressure.
- Heal: 1 MP to heal 1d3 HP
- Blast: 1 MP to deal 1d3 damage once
- Protect: 1 MP to reduce all damage by 1 for the duration
- Enchant: 1 MP to add 1 damage for the duration, or 1 to the chance to hit
- Curse: 1 MP to reduce an enemy's TR or PR by 1 (POW roll required)
- Uncanny Ability: 1 MP to add 1 to a stat, for the purpose of accomplishing a task (sneak, persuade, search, etc.) with preternatural skill
source https://rpg-tinker.blogspot.fr/2017/12/too-many-hacks.html