Infight happens when a monster is damaged by another monster. Monsters are normally immune to projectiles from monsters of the same species, but they can be damaged by a different species, the blast damage from an exploding attack, and hitscan attacks. Further refinement to damage-inflicting behavior between monsters can be obtained with custom damage types, and the actor flags DONTHARMSPECIES, DONTHARMCLASS, NOINFIGHTING and NORADIUSDMG, and more.
But infighting itself can be modified with the infighting console variable. It is possible to affect it in MAPINFO map definitions with the "noinfighting", "normalinfighting" and "totalinfighting" keywords.
- No infighting means that monsters will never infight, although they will still suffer from friendly fire.
- Normal infighting is the standard behavior explained above.
- Total infighting removes the "same species protection" and let monsters be damaged by projectiles from their kin, triggering retaliation.
The DOHARMSPECIES flag allows for monsters of the same species to hurt each other at all times.