Ancient Castle sidequest

This sidequest consists of two parts:

1. Collect the three keys scattered across the world to unlock the Ancient Castle level
2. Complete the Ancient Castle level

Key locations

• Green key: found at Santa's House, after completing level 2-2: Frosty Mountain through its secret exit. The exit is plainly visible halfway through the level, and can be reached by bouncing off of the Snowbird enemy below it.
• Red key: found at the end of the secret level 1-X: To The Top! That level must be unlocked by exiting through the secret exit in level 1-2: Forest of Secrets, which requires a double-jump to reach; see the Walkthrough for more details.
• Blue key: found in level 4-2: Great Descent. The key is located along the left wall.

Completing the Ancient Castle level

This is a large level full of various paths you can take. Your goal here is to find and pull three levels: one red, one green, and one blue. Once you've pulled all three levers, the exit in the top-left corner of the castle will be available.

The levers are in the bottom-left, bottom-right, and top-right sections of the level. The bottom-right lever will require first hitting a switch (after entering a door near the entrance of the level), which raises the water level.

At the exit of the level is a permanent powerup: a pair of Winged Boots. Collecting these unlocks the trophy and grants you the permanent double-jump ability. If you pick up a double-jump powerup (the green powerup), you'll be able to triple-jump, which grants another trophy.