ZDoom

OK! Thanks Bio Hazard and Graf, all is good now. It works exactly like that, I just needed the monster to be behind a wall and not visible to the player (or player not visible to the monster in 360° context?).

Before the player makes any noise, the deaf monster will not react until the player is within the monster's 180° field of view. The monster will not react to any noise as long as the player is not within 360° fov. After making a noise, the player will get the monster's attention even if the player approaches the monster from behind, the 360° fov "see" of the monster has been activated by the noise.

I never said that! But 'deaf' isn't really the correct name for this option. The internal 'ambush' comes closer to how they behave.

A 'deaf' (or 'ambushing') monster does wake up when it hears a shot and can see the player. Sight in this context means 360° field of view. The flag just prevents monsters from waking up when they are in a part of the level that can't be seen by the player, that's all.

Yes, deaf monsters aren't really "deaf" and graf says it's not a bug

I suspect that this isn't a bug, it's probably something I've forgotten since my editors became rusty, but here goes...

Why can't I properly flag a monster as deaf? I've tried zdoom 63a and 96, both doom2 map format and zdoom-hexen format, and a monster with the deaf flag set can hear a pistol shot and turns to chase the player. Tried a decorate monster too, with the +Ambush flag, same result. Anyone else have this problem???