The Undead Cyclops' Room is a sublevel of Wizard Castle Interior, and the second boss room on that level.
Upon entering you must advance until you see a cutscene where the Undead Cyclops comes out of a hole in the ground on a platform while holding a coffin. You must attack the Undead Cyclops, and after some time, you will find out that inside the coffin is the Undead Groom, who you can not attack directly. To continue you must defeat the Undead Cyclops and they will turn into angels, leaving behind a Boss Chest. After you collect the gold, you then continue to the crystal room to unlock the door to the Necromancer's Room.
- Wooden Mace - Before you exit, look for a dig spot made of bones on the floor. Dig this and you will find this weapon.
- The dig spot here is the only dig spot made out of bones.
- You won't be able able to access the dig spot if the coffin after killing Undead Cyclops falls over it.
- When you enter you can see the Eye Gate from the end of Cyclops' Cave.
- In the background you can see the skeleton of the Dragon and Sock Puppet.
- In the foreground you can see a fossilized Fire Demon in a crystal.
- This proves that Fire Demons aren't humans wearing masks
- This is the only level in the entire game where a heart beating can be heard.