Completing the dungeon awards you with the Skull Seal and the Necro Rod.
The easiest way to complete the Skull Maze is simply to follow a map. This will prevent you from going in the wrong direction, or allow you to find all the chests and secret areas if you want to. The map itself is located just below this text, and you start the dungeon at the bottom middle.
Map of the Skull Maze
Map symbols explainedRed: Torchlight. You can choose to light these to get a better view if you want to.
Pink: Entrance to a secret area.
Green: The goal of the maze. Once you get here you "win" and get teleported out.
Orange: A Sacrificial Shrine. Be careful when interacting with this, because you will have to sacrifice one permanent Heart when doing this.
Blue: The place where you start the Maze.