rooms with heavy objects and switches that change the direction of gravity, doors on ceilings, stairs up the walls, the trap resets itself
"the room is scattered with large stones and what appears to be splinters of bones, battered armor and broken furniture..."
then make exploding runes that look just like the switches,... and some craters for the rules lawyer
also some doors could send players to a random room, ....with a random direction of gravity
as soon as they think they FINALLY have it figured out.....
loot that drains levels when you pick it up, isn't there some kind of evil arrows that do this?
include puzzles that obviously copy Indiana Jones, or any movie the players will know, then make what happens in the movie the worst possible choice