Chaotix

The Chaotix were originally a team of Freedom Fighters who are allies of Sonic the Hedgehog. The team was lead by Knuckles the Echidna and consisted of
 * Vector the Crocodile
 * Charmy Bee
 * Espio the Chameleon
 * Mighty the Armadillo
 * Ray the Flying Squirrel

Former members prior to Worlds Collide included:
 * Julie-Su
 * Saffron Bee
 * Heavy
 * Bomb

History
Chaotix appeared in the Worlds Collide crossover, where they were a trio of detectives rather than a Freedom Fighter group and only consisting of Vector, Charmy & Espio.

Chaotix was among the friends of Sonic abducted by Copy Robot-on orders from Dr. Eggman and Dr. Wily-and turned into Roboticized Masters. (Sonic Universe #51)

They were subsequently the first three Masters to be restored to normal by Mega Man's Mega Buster, which had been modified to duplicate Sonic's Spin-Dash ability. In gratitude, Chaotix located Proto Man in order to aid him in locating the Wily Egg. (Mega Man #26 & Sonic Universe #53)

Due to the alteration of Sonic's world, Chaotix's history was permanently altered. Like their appearance in Worlds Collide, the group was a detective agency, rather than a Freedom Fighters group. Though they aren't members, Knuckles, Mighty and Ray are allies of the group.