I think some trash should dissapear once a boss is dead. Like for example if a raid kills Shad'har and then raids off, next day the trash from the start of the hole until after Shad'har shouldn't still be there. Or for example, if the raid kills Xanesh, all trash from start to Xanesh should be clear next time and only be trash from Xanesh to Vexiona. I thought it always was the case in other raids... could be wrong tho, but I didn't felt like there were so much trash in Eternal Palace when going back next day.
Anyone know if the memento drop is 100%?