The new design also introduces a very "extreme games" style move system where players can pull off special moves to score additional points and to boost power. These moves can be pulled off with button and D-pad combinations while leaping in the air as well as grinding on some rails. This element really puts the Sonic 3D model through its paces, because it would be tough to offer the same move set through animated sprites.
And, of course, there's the dual screen aspect. The development team use the two screens as one display -- it's not the first time this technique's been used for a Nintendo DS game, as titles like Metroid Prime Pinball and Bomberman have beaten Sonic Rush to the punch. The added screen increases the vertical real estate of the levels so players can explore high and low, and the camera system does a great job keeping track of the hedgehog and follows him from screen to screen with very little disorientation placed on the gamer. The boss battles are relegated to a single screen, but the developers push the Nintendo DS system's 3D capabilities much harder in these instances to build some very creative bad guys to fight.
The dual screen aspect also disappears when players jump into the single cartridge multiplayer race. Here, players can choose either Sonic or Blaze the Cat and compete to race through any of the unlocked levels in the game. The upperscreen is the gamer's view, with the lower screen keeping track of where the opponent's running. To cut back on processing time, the 3D model of the opposing player is removed in favor of a much more simple icon that plots the point on the map where the competition is in the level. The multiplayer version doesn't slow down compared to the single player outing, playing just as fast and exaggerated as the solo adventure.
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