Israphel's Castle was a fortress located in a giant cave underneath Terrorvale. It was where Israphel took Daisy Duke, having kidnapped her from Terrorvale. Israphel's Castle was the first place Xephos and Honeydew encountered the boss characters.
The Zombie Boss was fought coming out of the front door, crouching and holding an axe. The Creeper Boss was encountered on the glass roof of the castle, and blew up when fought upstairs, using TNT. Behind the castle is a very long, dark, winding tunnel, leading to the Cave of Terror, and a Hellgate. After the Battle under Terrorvale, the heroes go follow the path and to their Hellgate. However, they are unable to chase Israphel because he teleports them to a strange island.