I Highly doubt it's anything like Pokemon chaining (gotta look that up). Anyway, In Darkspore, Once you complete a level, you are given two options-Quit and get your rewards, or Risk it all and Chain. (And there's a timer to make you hurry up.) If you quit, you will receive your chance item with the Medals you've earned from the level (4 medals you can get-Bronze, Silver, Gold, but ...