Ultimate Castle Challenge

Castles - Masterpiece Set, renamed Ultimate Castle Challenge in the GBA remake, is the Extra Stage of World 6 in Super Mario World 2: Yoshi's Island and Yoshi's Island: Super Mario Advance 3. Like every other Extra Stage, this level's playable Yoshi is the green Yoshi.

Level areas

 * Part 1: Caged Ghosts and a Mace Guy are present.
 * Part 2: Moving platforms over and under spikes and thorns are present. Some Spear Guys appear here.
 * Part 3: Flatbed Ferries under and over thorns, super-fast platforms that head straight into spikes. An Egg Block appears in this room, as well as some Dangling Ghosts.
 * Part 4: The player rides on a flatbed ferry and avoid being knocked by Sluggers and Green Gloves.
 * Part 5: The player ground-pounds through a long tunnel and avoid being knocked into thorns lining the walls.
 * Part 6: It is similar to Part 5, but with thorns absent.
 * Part 7: The player rides an underwater flatbed ferry going under thorns, and the player reaches the Goal Ring for the final part.

Background music

 * Parts 1-3: Fort/Castle
 * Parts 4-6: Athletic
 * Part 7: Bonus Area

Trivia

 * In the second area of this level, the tracks that the Flatbed Ferries travel on spell the word "YOSHI" in worldwide releases, but in Japanese versions, they instead spell "YOSSY" (an alternate romanization also used for the box art). This was also the case for the remake.