Ben 10: Alien Force (2008)

S3E20 The Final Battle (2)

Ben, feeling helpless, boards Vilgax's ship for a showdown to thwart the invasion of Earth once and for all. In a surprising twist, Albedo hands Ben the Ultimatrix, allowing him to access his previous aliens and their upgraded forms. This final confrontation sets the stage for an epic clash between Ben and Vilgax.