Chilly Castle is a race track in Sonic & All-Stars Racing Transformed and the second track of the Emerald Cup, representing Billy Hatcher and the Giant Egg for the Nintendo GameCube.
The track takes place on a snowy night at Blizzard Castle, with racers driving through a twisty village before taking a tour through the eponymous castle itself, avoiding roaming Crows. The racers soon enter a tunnel, only to fall through a gaping hole that drops them into a crystal-filled underground river that they must navigate in boat form. The river will eventually lead back to the village and the finish line.
Bantam Scrambled, Rolly Roll and Chick Poacher make cameo appearances at the first fork of the track. Ironically, Billy Hatcher himself is nowhere to be seen, seemingly suggesting he was intended to be playable and cut late in development, or planned for downloadable content which did not happen.
The music that plays here is a remix of the Day 2 theme of Forest Village, which then transitions into the game's boss theme.