gen1recomp/docs/guides/rulesets.md

Rulesets

OPTIONS > RULESET picks which set of Gen 1 battle behaviors to run. Both rulesets share the same damage formulas; they differ only in whether the original's quirks are kept. The setting persists in options.lua, and mods can register their own.

gen1_faithful

The default. Reproduces the original cartridge, famous bugs included.

Rule	Behavior
oneIn256Miss	A 100%-accurate move still misses on a roll of 255
critUsesBaseSpeed	Crit rate reads base speed, not the current stat
critIgnoresStages	Crit rate ignores stat stages
focusEnergyBug	FOCUS ENERGY quarters the crit rate instead of x4
enemyUnlimitedPP	Enemies never spend PP, so they never Struggle
hyperBeamSkipRechargeOnKO	HYPER BEAM skips its recharge when the target faints
randMin / randMax	Damage random factor 217-255

modern_clean

Keeps the formulas but removes the notorious quirks.

Rule	Behavior
oneIn256Miss	Off: a 100%-accurate move always hits
critUsesBaseSpeed	Unchanged: crit rate still reads base speed
critIgnoresStages	Off: stat stages count toward the crit rate
focusEnergyBug	Off: FOCUS ENERGY raises the crit rate as intended
enemyUnlimitedPP	Off: enemies deplete PP and Struggle when empty
hyperBeamSkipRechargeOnKO	Off: HYPER BEAM always recharges, like Gen 2+
randMin / randMax	Damage random factor 217-255, same as faithful