Arelith

1. level up warlock
2. Cast cloudkill spell
3. Con damage per round is refreshed per round and do not stack .
4. Monster still alive after staying in cloudkill for eternity without immunity.

Per Kalopsia, there is a penalty stat-cap of 30; meaning monsters with 31 or more CON won't die to Cloudkill alone. However, the spell is still bugged in some way. I reported the same thing before.

viewtopic.php?f=12&t=38802&p=304815&hil ... ll#p304815

I test this spell in surface and PGCC, on a summoned dire bear(5 level) with 22 CON, it's CON ends keeps jumping from 11 to 14, takes merely 4~5 rounds with a empowered cloadkill. If that's a matter of attribute penalty cap, that would be awful because spell like Infestation of Maggots rely on the attribute penalty to work.

update:
Infestation of Maggots can successfully decrease the CON down to 3 and kill the bear. While cloadkill can't decrease the bear's CON lower than 11, empowered or not. I'm pretty sure these is a secret cap for cloadkill it own, or the attribute damage system.

A fix for this is live now.