@jsalsb
Not really - apart from the hypothetical ones. There is a bug concerning the lava pool in Skull Castle (the one underneath the niche where the relic is situated). At some point there it is possible to fall through the lava, but not all the way to the bottom. Dropped items, however, fall all the way to bottom. So in theory one could go to the pyramid, retrieve the champions' kays, go back to Skull Castle and drop them in the lava pool there. That would be a game killer - but one would have to work hard to achieve it.
