/vr/ - Retro Games

Can anyone recommend some good WADs that feel particularly "vicious"? I'm not really talking about relentless slaughter fests, but I just got done playing zone 400 and was really quite taken with some of the mean traps, sadistic enemy placement and map design that minimized safe spots and forced me to be mobile. Despite not having huge enemy counts, it ended up being pretty intense. Map 23 of Speed of Doom is another one that comes to mind as similar.