Sonic Adventure 2
Sonic Adventure 2 is a platform video game released for the Dreamcast in 2001. This game is the sequel to Sonic Adventure. In 2002, a remake of the game, Sonic Adventure 2: Battle, was released for the Nintendo GameCube. The game was the tenth best selling GameCube game of all time. 
Playable Characters change
Playing style change
Sonic and Shadow change
The levels for Sonic and Shadow are the classic "Get to the Goal" levels. They are very agile and can use shortcuts made by enemies and later, Rings. They have the ability to become Super, using the Chaos Emeralds. The levels are very similar to the original Sonic the Hedgehog game, except of course it is three dimensional.
Tails and Eggman change
These two are also "Get to the Goal" levels. A difference from Sonic and Shadow's levels are that they are "mech", in other words they use machines to move around. They fire bullets from their Cannons.
Knuckles and Rouge change
These levels are treasure hunting levels, where they have to find Master Emerald shards, Chaos Emeralds (in Rouge's case), or Door Keys.