Marvel's Avengers Assemble - Season 2 Episode 21 -

Now that he's an Avenger, Ant-Man "cleans his ledger" by bringing down bad guys that he's previously built tech for. However, his quest for redemption forces other Avengers to face the burdens of their past and when they discover Dr. Spectrum is on Ant-Man's ledger, the Avengers are forced to face one of the most powerful members of the Squadron Supreme before he destroys the world.