dot-effects

dot-effects holds what is currently true of an entity beyond its health: burning, bleeding, crit-boosted, slowed, stunned, invulnerable, marked, incapacitated.

Requires dot-core.

One document, not twenty classes

Count the status effects a team shooter and a co-operative shooter ship between them and you get about twenty-one. Nineteen are the same six fields with different numbers: a duration, a periodic amount, a multiplier on damage taken, a multiplier on damage dealt, a multiplier on movement, and a flag.

effects.define(DotEffectDef.burning(&"afterburn", 3.0, 10 * 64))
effects.define(DotEffectDef.damage_buff(&"crit", 3.0, 5 * 64))
effects.define(DotEffectDef.invulnerability(&"invuln", 8 * 64))
effects.define(DotEffectDef.speed(&"adrenaline", 1.4, 15 * 64))

It never touches a health value

A burning entity does not lose health here. The manager reports an amount and the game applies it, through whatever it already uses:

effects.damaged.connect(func(entity, amount, type, source):
    health_of(entity).apply(DotDamage.make(amount, type, source, tick)))

That is what lets a slow, a stun or a speed boost work in a game with no damage system at all — and it means an afterburn tick goes through the same lag compensation, armour and friendly-fire rules as every other hit.

Down rather than dead

effects.rules.downed_enabled = true

# One place decides, rather than every damage site:
var what := effects.report_zero_health(entity)
if str(what.value) == "down":
    player.play_downed()
else:
    player.die()

A downed player bleeds out over ninety seconds, is picked up in five, comes back with 30 health, and the third time is the last.