In the quest I'm making, I want there to be a special key in each area's main dungeon that allows the player to open a specific door in the overworld. The only problem is if I make it a regular key, they might use it in the dungeon, and if I make it a big key, they might use it to get to the boss early (and the overworld is a different level). Is there a way to make it so that a key picked up in a dungeon only works on a door in the overworld?
Also I forgot to mention that the key needs to be one-use, since there will be multiple doors and multiple dungeons that have keys.