SmashBro99
Smash Champion
One of my favorite old genesis games, I wish they had done more with it. The story is in the video. The Kid Chameleon uses helmets he finds in blocks as powerups, which give him many different powers. (All descriptions taken from http://kidchameleon.wikia.com/wiki/Main_Page )
Each helmet also has special diamond powers, diamonds are items you collect throughout the game (Think of Mario's coins or Sonic's rings), you can carry up to 99 at a time.
http://kidchameleon.wikia.com/wiki/Diamond_power