They splat on the way down. Their loot lands on the next level though, which gets interesting when you chasm kill something that drops a flame potion into flammable terrain. You see the latter happen occasionally in demon halls when you chasm kill scorpions. Breakable when thrown items break when they fall down a chasm so you end up spawning potion effects at random places around the next level.
Oh, crap… I just assumed that they spawned on the next floor like items so I avoided doing that in case I overwhelmed myself later on lol
They splat on the way down. Their loot lands on the next level though, which gets interesting when you chasm kill something that drops a flame potion into flammable terrain. You see the latter happen occasionally in demon halls when you chasm kill scorpions. Breakable when thrown items break when they fall down a chasm so you end up spawning potion effects at random places around the next level.