Atramedes spawns in the lava when the bell is rang instead of spawning in the air. It does not fly up even after spawning so, if you kill it, it’s dead in the lava.
If Nefarian dies while flying, his corpse does not fall down. Prior to today (or the level squish), his corpse would fall down if he died while flying. Now he’s just a floating corpse.
came here because he wouldnt actually spawn for me at all 
not sure if thats because its been taken down to be worked on or something
edit: left and re-entered and the cutscene finally started - he also spawned in the lava, then i jumped in the lava trying to kill him on the way down. He disappeared before i could get a spell off, and when i ran back he was where he was supposed to be