Watch for enemies and lines of rings. Collect as many rings as possible while defeating enemies to build up the Fever meter. Once full you can activate a bonus round which allows you to collect even more rings. Red rings are worth the most, and are needed to unlock new characters and stages. Each time you play decreases a charge meter that is filled either by waiting or by spending 40 red rings. Connect the game to Facebook or Twitter to get free rings. You can also watch advertisement videos and completing offers on Tapjoy to also get rings.