fire_penalty

[Deadlock989]

This is a parameter in the attack_parameters prototype. In vanilla, only the flamethrower turret uses it.

What does it do?

[Bilka]

copy paste from source

/** Used when searching for the nearest enemy to penalize units that are burning. */

So I'd say it makes the flamethrower turret prefer non-burning enemies over burning enemies. Burning in this case: has sticker that has a "spread_fire_entity" attached to it.

[Deadlock989]

Cheers mate.