Sonic Heroes

Sonic Heroes was a game released in 2003 for the Gamecube, PS3, XBox, and later PC. The game's story centered on how four teams each wanted to find something. Depending on which team was selected, the style of gameplay changed notably. They were all searching for, or otherwise involved in, who they believed to be Robotnik. In many way, this game represented a return to the roots of Sonic the Hedgehog, having seven worlds (each with two normal 'acts' and one boss fight) and a final boss showdown, plus a hidden 'actual' final showdown.

Each team had three members: Speed, Power, and Flight. Any of these could be switched into at almost any time, making tag-team fights (where one member would expose a weak point, and another member exploit it) not only possible, but necessary.

Team Rose
Team Rose was composed of Amy Rose as Speed, Cream (and Cheese) as Flight, and Big the Cat as Power. Team Rose was searching for things; Cream was looking for Cheese's kidnapped brother, Chocola; Big the Cat was looking for his companion Froggy; and Amy Rose was on her eternal quest to find Sonic.

Team Rose did not intentionally seek out Robotnik; rather, two of those searched for (Chocola and Froggy) contained data about the Chaos force (Chocola being a Chao, and Froggy having previously been a host for a Chaos Emerald), and Sonic managed to get himself into trouble with Robotnik anyways.

Team Rose's gameplay was easy. For example, their missions were often in shorter versions of the 'full' levels, without the miniboss scenes or the full load of enemies. When using their 'Team Blast' attack, Team Rose destroyed all nearby enemies and received a levelup each, a speed boost, and invincibility.

Team Sonic
Team Sonic was composed of Sonic as Speed, Tails as Flight, and Knuckles as Power. Team Sonic, as usual, was off to defend the world from Dr. Robotnik.

Team Sonic's gameplay was of normal difficulty; most missions were timed, requiring an all-out run towards the goal ring. Their Team Attack destroyed all nearby enemies and upgraded Sonic's attack for ten seconds.

Team Dark
Team Dark was composed of Shadow as Speed, Rouge as Flight, and E-123 Ω. Shadow was after Robotnik to regain his lost memory, Ω was after Robotnik for revenge for shutting him down, and Rouge was mostly making Shadow and Ω work together to protect her own skin. Unlike most other teams (where the Speed member was the leader), for Team Dark, Rouge (their Flight member) was the leader.

Team Dark's gameplay was of hard difficulty; although their missions generally resembled Team Sonic's, their requirements were harder and they had to fight more robots to do their missions. Against that, they had the most powerful Team Attack: Shadow froze time for 10 seconds, while Ω used a Chaos Emerald-powered blaster cannon to destroy all nearby enemies.

Team Chaotix
Team Chaotix was composed of Espio as Speed, Charmy as Flight, and Vector as Power. The members of Team Chaotix were a detective agency who were hired by the real Dr. Robotnik to find out who the impostor was.

Team Chaotix's gameplay was of very hard (or 'oni') difficulty; their missions were the most exacting requirement-wise, and often required restarting the level and replaying it ad infinitum until the prescribed goal was finished. They had a weak team blast: although they destroyed all enemies in a local area, instead of powering up, they received rings (5, 10, or 20, randomly), and would receive rings from any enemy destroyed within the next 10 seconds.

Music
Much of the music in Sonic Heroes was composed and performed by Crush 40, a role they would resume in Shadow the Hedgehog.