Monster won't leave corpse
 

Why would an npc not leave a corpse? I made one involved in a quest and it's not leaving a corpse when it dies.

does npc has loot?
if npc has no loot, the corpse poofs in 15 seconds or less (based on rule in rule table)

it has loot

If the NPC is a merchant, they will not leave a corpse either (class 41). May also be true for adventure merchants, GMs, and other odd non-player classes.

You can adjust the value in the rule_values table for the rule "NPC:EmptyNPCCorpseDecayTimeMS". Adjust it to however long you'd like empty corpses to stay around. A value of 5000 would leave them for 5 seconds (as it's measured in milliseconds).

Then npc has loot, it is a warrior, and it doesnt have a merchant id either.

Did you restart your server after you added the loot table for him? New loot tables don't take effect until the server is restarted. You can tell if he actually has loot or not by doing a "#npcstats" on him. If you don't get any loot or cash showing from that output, then he doesn't have loot and will require a server restart for the loot to get added to him.

Oh yeah, and also if you #kill a mob without hitting it at least 1 time, they will never leave a corpse.

Yeah I restarted server first. I can tell he had loot because I did #npcloot show and he was wielding the items as well. I did #kill, #damage, and straight meleeing but none of them changed it

Ok, we are running out of possible causes for this issue. Please describe exactly what the quest script is you are trying to use for him and other related NPCs if any. Post them if you want.

The last thing I can think of that will poof a corpse is if an NPC or anything other than a player lands the killing blow. If the final kill doesn't come from a player, the corpse will poof immediately.

It's simple. You kill a mob and it pops him. Then you kill him

Is your GM flag on? Only other thing I can think of.