FusionFall Heroes was a free-to-play game hosted by CartoonNetwork.com. It is a sequel/spin-off to the MMORPG Cartoon Network Universe: FusionFall. The game was the last official use of the FusionFall IP.

When Planet Fusion attacked the Cartoon Network Universe, a legion of kids rose up to help defend the world. But what were your favorite Cartoon Network characters up to? It turns out they decided to fight the fusion monsters right at their source! When they weren't busy helping the resistance, Cartoon Network's greatest heroes formed small, co-op fireteams to assault the Fusion spawning grounds. If they succeeded in their missions, they would strike a huge blow against Lord Fuse and his army of evil minions. Empowered by the rare element Dextronium, the heroes aim to destroy these monsters and take back their planet.