In Vanilla JITD:
Quest 7 The Black Blade yada
1) There is a guardian beast that acts like a master beastman, but you cannot kill it (unless you wield the blade of light). The OL used this creature to camp on chests and was going to use it to camp on the blade of light load. Can you open a chest if this guardian is on one? Theoretically, you could make the game not winnable if you can get the guardian to camp on the blade of light load and not the heroes pick it up.