Daedalian Keys will appear only after starting the quest "The Daedalian Keys". These are small keys floating in the air. There are a total of 16 of them and all of them are located in Hogwarts Castle. When you approach one of them, it will start flying towards the corresponding House Cabinet, which should be somewhere nearby. Follow it, interact with the cabinet and slap the key when it hovers over the lock. When you do so, the cabinet will open and you will receive a House Token that you can throw into the chest located in the common room of your house. Once you throw in all 16 house tokens you will receive a unique outfit for your house.
