Manin

- The timed switch puzzle demands a lot more of you than everything else in the map. Because monsters harass you the whole time and texturing is uniform, it takes disproportionately long to figure out the sequence of lowering lifts and the proper "trick" to reaching the last one in time.

- In the sergeant trap following that, you simply hide in one closet and block its spawns, and then pick off sergeants from the other closets one by one. I didn't find that entertaining to do, but you pretty much have to otherwise they can shred you. 

- When you try to return from the blue key itself, a monster might stand on the lowering lift you need to take. It can prevent the lift from rising a few times by bonking its head on a ceiling. The lift would have benefited from monster-block lines.