Ed holding the key.
Ed's Key is an item that was only seen in "Key to My Ed." Edd found the key and suggested that the Eds return it to its owner. Eddy, however, wanted to see what it opened, but he failed on numerous occasions to find out. Eddy eventually gave up and decided to hold the key for ransom. In the end, this led to a brawl, as none of the Kids cared about the key, and all instead attacked each other over various items they were missing. The rumble attracted the Kankers, who chased the Eds to Ed's house. There, the Eds realized that the key belonged to Ed and it had fallen out of a hole in his pocket earlier. The key opens his back door, and probably the rest of the doors in Ed's house.