Mordred's Fortress

Mordred's Fortress is where Mordred is hiding Elyana. It is found in a separate dimension which can be accessed via the Crystal Gate.

Role in Astro-Knights Island
Mordred's Fortress is where Mordred build his robot. When you first enter the fortress, Mordred will pose as the princess and will take the mystical weapons of Arturus from you. He will then reveal his true identity, and will enter his throne room. You then must solve a puzzle to enter the room. After that, you will have to fight Mordred in his throne room. After you defeat him and rescue Elyana, Mordred will remain trapped in his fortress until he is sent to Erewhon.

Trivia

 * The door to this fortress is sealed with a riddle. You must flip over all the flaps that make up the door and each time you click one flap, the flaps above, beneath and next to it will flip over.
 * Mordred must have used advanced technology to create this fort, due to the fact that it is in another dimension.