Season 3: The Viltrumite War Commences

The third season dives deeper into the consequences of the Viltrumite threat and Mark's escalating responsibilities. Mark continues to grapple with the guilt of killing Angstrom Levy and the immense pressure of the Viltrumite ultimatum. As the alien threat looms, Allen the Alien, working for the Coalition of Planets, is tasked with finding a way to defeat the Viltrumites and tries to recruit Mark. Meanwhile, the GDA, led by Cecil Stedman, begins taking drastic measures to prepare Earth for the inevitable war, including using captured villains as weapons. Mark's half-brother, Oliver, ages rapidly and begins training as a hero, while Mark finally allows his relationship with Atom Eve to blossom. The season's climax brings the full force of the Viltrumite Empire to Earth with the arrival of Conquest, a brutally powerful Viltrumite veteran, sent to ensure Earth's conquest. Mark and Conquest engage in a horrific, city-leveling battle that pushes Invincible to his absolute limit. Though Mark manages to defeat and brutally kill Conquest, the victory comes at a massive personal cost, confirming that the war for Earth has truly begun and Mark must be prepared to be more brutal than he ever imagined.