The restriction that you can only complete the thief or the assassin
questlines has been removed. You can now do both, meaning that LQ79 and LQ90
are now possible by the same person. All previous completion data has been
wiped, so all mortals are eligible for these quests, even if they've already
been awarded before. Obviously, there's no point in getting the same LQ twice.
Trilloch himself has received an across-the-board combat upgrade, and will
stay on the ground for longer periods of time to make use of it.