(red rectangle is the targetted monster)
Hitscan testing is next up. Basically after I have the target I just move from the players sub-sector to the next based on the segments that line intersects with, doing actor and wall collision test on the way(Ben would know what I mean). The monsters just have the player set as a permanent target. There won't be any monster in-fighting as I think it would be more trouble than it's worth. Also monsters can tell if they'd hit the player or another monster before any damage is assigned, unlike Doom which fires first and asks questions later.
Also that'll probably be the zoom level the game is set to. I want there to be plenty of monsters on screen, but not choke the frame rate at the same time.