when you do the boss of Blood, Frost, and Death timeline, after killing it, if you don’t speak with the quest minotaur in the cage, and just portal out, you can do the boss again. you can just infinitely farm its uniques. i think its a pretty important bug to fix inmediatly, specially in trade.
idk if there’s any other boss with a quest interaction after the kill, but if there is, it might suffer from the same exploit.