Looks like server went crash.

Something in the monster lotto might be causing it, last couple crashes I was around in were during a ML.

Hm...

Can you PM me with as much info as you can remember on what you were doing or trying to do just before the crash?
What level you were at?
What stage of the battle?
Who you were against?
anything else you can recall.

The last dozen lines in the log relate to the 3 players in the ML so there is a good chance you are correct, especially if this is a repeat event.

Any specific info you can give will help to narrow this down.

The last crash happened while I was fighting with my character Tellurium. I don't exactly remember the enemies, they were 3, one of them was a gargoyle and I remember an arch-templar, probably a barbarian?
Crash happened moments after I attempted to curse them (might've been another spell, memory is foggy now), but I'm pretty sure it wasn't the spell itself that caused it, since it would've crashed before I got to see the cast.

Perhaps the bug could be found more easily if when the enemies are spawned for monster lotto the npcs log themselves. This would allow us to know which npcs where around just before the next crash in ML. Then we could test each npc afterwards to figure it out.

Looks like:
Tellurium had Barbarian, Urien's Apprentice and Gargoyle.
Smeyan had Merchant, Merchant and Abandoned Skeleton - Start completed 3 of 9.
Namely had a Greenling Veteran - Start completed 2 of 9.

Last line in the log had Eakur killing the Greenling Veteran.

It is probably what happened after that that was the cause but because the logs normally are written after an event, not before it that I can not see that specific action.