Sonic Rush is a 2005 platform video game developed by Sonic Team and Dimps for the Nintendo DS as part of Sega's Sonic the Hedgehog series. It is a 2D platform game, similar to earlier games in the series as well as later ones like Sonic Advance. Levels in the game are side-scrolling and displayed using both of the DS's screens. However, boss battles, the main characters, and a special stage are rendered in 3D, creating a 2.5D effect. The game's storyline follows the intertwining adventures of a new character, Blaze the Cat, and the series' main character, Sonic the Hedgehog. They respectively battle Doctor Eggman and his doppelgänger Eggman Nega at certain points.