Chill Hills

Chill Hills is the sixth world that the player will encounter during a run. (Unless the player does World 6 Darkness) Pyro Droids fittingly do not appear naturally, while Cryo Droids and their variants are much more common.

Rapid-Fire Droids and Switch Droids make their debut, although Switch Droids are quite uncommon in Chill Hills. If you plan on doing late-game Darkness, it is recommended that you kill the Friendly Droid here or in the previous world.

Environment
Chill Hills resembles a polar area. It has a white, snowy ground and gray walls that are tinted blue. Environmental objects include large ice spikes and igloos with possible friendly droids inside them.

Chill Hills's environmental hazard is water. It is visually and functionally similar to the water found in Lush Jungle. However, there are water bodies in Chill Hills where some portions of the water are naturally frozen while some portions are not.

Freeze/Melt buttons are fairly common here, with some rooms even having multiple buttons. The Candy Sword can still freeze the water here, so keep it in your inventory for this world.

Ice spikes and water walls appear in Chill Hills. They are water and can be frozen and melted, but they do not deal any damage to the player if walked through while melted. When melted, they are translucent and do not collide with anything. However, when they are frozen, they become a solid obstacle. They can be used to block projectiles and in some cases stop Droids from chasing you through the walls.

Trivia

 * There is a room where an igloo spawns. Inside the igloo is a Friendly Droid.
 * The song that plays in this world is called Sonic 3 OST - Ice Cap Zone Act 1.