ColdKeep is first entered through DeepTower, either from a hidden passage in the boss room or by exiting on the passage to the left at the base. If the player uses the concealed exit, they can receive an extra jump upgrade, found on a longer branch.
ColdKeep consists of stationary cannons and crushers. Most of the area is covered with snow. The sky is black with white dots. Some grey swirling shapes can be seen in the foreground.
This location is also the player's first encounter with blue energy clusters. A cannon placed on the platform above the crushers is positioned to fire at the bottom cluster, showing the player that it creates a platform. The player must use this maneuver to reach NightClimb.
To the right of the screen with the blue energy clusters is a building whose interior remains hidden until the protagonist enters. Inside this grey building is a boss battle.
- A heart can be found when the player enters ColdKeep through the bottom of DeepTower. The protagonist should jump from one of the top ledges to reach it.
- A second heart is found in a concealed opening underneath the middle of the row of three cannons on the ground. The player needs an ice shot to destroy the middle cannon so that the protagonist can fall through the passage it blocks.
- A blue orb that increases jump height can be acquired by passing through the hidden path in the above room in DeepTower. Small arrows pointing to the left from the tree trunk's design indicate the presence of the passage.
- After the boss is defeated, the player can obtain a blue orb that allows the protagonist to stick to ceilings.