Icecaps

The Icecaps are an arctic wasteland in Sonic's dimension, consisting of extremely cold regions and large mountains made of ice; this frozen area is known to be dangerous, particularly within the caves below, which are filled with ice spikes and collapsing mounds of snow. In the "Dimension" saga, the Search for the Sacred Elements starts here, as the alliance of heroes begins seeking out the fire element beneath the surface level of ice. However, the first to claim this element turns out to be Mr. D, who uses it to begin shooting large blasts of fire everywhere—causing the caves themselves to begin melting rapidly; Mr. D's new destructive abilties ultimately reduce a large portion of the frozen regions to water, which leads to Mario falling in and nearly freezing to death. Eventually, Sonic, Calvin, and Hobbes use one of the Icecaps' steep mountains to ride the Time Machine downhill and ram into Mr. D with it, finally subduing him for a short while. The alliance then uses Dib's watch to escape, just before Mr. D uses the fire element to trigger a tremendous explosion, which undoubtedly reduces even more of the land to melted ice.