There's this bit in LoZ: Oracle of Seasons that I actually never figured out.
It's a room with a blue floor full of squares on something called, like, the Hero's Path, and you start on this yellow square walking around the room, trying to turn all the blue squares red. Not only could I never complete it, but it was specifically designed to make it so that EVERY DAMN TIME you completed it wrong, there was always one- and ONLY one- square left you didn't get.
The programmers for those LoZ Oracle of _____ Hero's Path segments were serious jerks. The other one, in Oracle of Ages, didn't even end on a treasure chest or anything- there's just some cryptic riddle and an old guy in a wierd room.