MegaMan Starforce (Ryuusei no Rockman in Japan) follows the journey of a boy named Geo Stellar (Subaru in the Japanese version) who encounters an alien from a race called the FMs, named Omega-Xis (Warrock in the Japanese version). They can merge into one being called MegaMan. Together, they fight Wave Viruses and other enemies to save the world.

MegaMan Starforce is in the vein of MegaMan Battle Network and serves as a replacement for it, but not a continuation. It is an RPG and you play on a grid. The difference is that it is in 3D and you see the back of Rockman rather than his side in battle. You attack with a MegaBuster and battle cards. Using a battle card (similar to a battle chip) will let you use a special weapon, have a enemy or ally attack, give you protection, or give you health, depending on the card you use.

MegaMan Starforce takes place 200 years after the EXE series in 220x. Networks are a thing of the past and the whole world is connected with radio waves. These radio waves have created a different world only seen with the use of a visualizer which are a special type of eye-wear that Geo / Subaru has. It is powered by three satelites: Pegasus, Leo and Dragon. People use Transers, similar to PETs, and are worn on the wrist. The FMs can live in the transer, but few people know of the FMs existance. Net Navis and cyber networs still exist, but humans rely on them much less and people no longer have Navi partners.

Throughout the game, enemy FMs approach troubled humans and promise them power to fix their lives, but they lose control of themselves and are taken over by the FM. Subaru and Warlock, however, are different and Subaru keeps full control and Warrock is not evil. To rescue these humans, MegaMan has to defeat them.