Oh yeah, sorry about that. CB has been in development for a little while. The playable characters are the genesis trio(Sonic, Tails, Knuckles) and also the knuckles chaotix characters(Espio, Mighty, Vector). It's got a wacky story, but I'll try to post that once it's been better demonstrated in the game. So far there are four zones: Crystaline Kingdom Garland Grove Mystic Oasis Polaroptic Powerplant
Here are some later game bosses in developement: Polaroptic Powerplant Boss A larger scale merge of the S2 and S&K deathegg boss. Doomday Boss
Robotnik figures out how to properly use the chaos emeralds creating this final boss.
And of course the helicore boss up top. Other zones: Hypnotronic Haven, Aurora Borealis, Deathegg, and Doomsday. Gameplay videos:
Here is the latest download: http://www.moddb.com/games/sonic-cb/downloads/sonic-cb-v20