Fall of Vilgax is the first episode of Ben 10: The Phantom Ship.
Plot[]
After all of the adventures had ended and all villains surely put to rest, Ben was ready to spend the rest of his life chilling and playing Sumo Slammers. He puts away the Omnitrix for good so nothing can get in his way. However, Ben was so wrong to think that all villains were gone. Vilgax was back, with an Omnitrix as a prize. Ben realises that's his, so he has nothing.
Ben struggles to figure out what he should do to stop him, but there's nothing. Suddenly, he's transported to an empty room with nothing but a glowing orb. He touches the orb, and he sees the future flash before his eyes. Afterwards, he gains the Phantomtrix. He describes it as a knockoff of a knockoff. This refers to the Phantomtrix basically being an upgraded Ultimatrix.
Ben decides to give it a test drive in battle against Vilgax, transforming into Feedback. Vilgax at the time had transformed into Shocksquatch, making the fight being easier than he thought. Ben described this fight as one of the easiest attacks against Vilgax. He says that Vilgax is a little off the edge today and what happened. Vilgax tells Ben that he's a fool to think he had won, and summoned an army of Fulmini warriors.
Ben says fighting these guys is a waist of time and decides to transform into Fasttrack to make the battle a quick one, however, they were stronger than Ben thought. The Fulmini warriors were angered and struck Ben down, transforming him back into himself.
Just as everyone thought this was the end, Rook Blonko comes in to save the day once again. Ben getting back up on his feet tells Rook that it's been some time since the last time they encountered each other. Instead of saying a similar thing back to Ben, Rook questions Ben's new Omnitrix. He doesn't even know anything about this new Omnitrix, but he tells Rook that Vilgax has the original and they must get it back
Ben and Rook hop into an upgraded ship he built from scraps and fly into Vilgax's new fortress in the sky. Ben transforms into Humungousaur so he could smash through all the defences in there. Ben encounters Vilgax as Rook stays and fights the Fulmini warriors. Ben transforms into Rath for the epic showdown against the old enemy. Vilgax transforms into Four Arms, then turns the Omnitrix to the side and presses it to transform himself into Ultimate Four Arms. Vilgax explains to Ben that with a little bit of modifications he was able to enhance the Omnitrix so he could obtain many different ultimate aliens.
While he goes on, Rath gets angered and annoyed with this and starts attacking Vilgax while giving him a piece of Rath. Vilgax is severely damaged not just by Rath, but most of the defences that backfired on him, causing him to decease. The Omnitrix, too, was beyond repair. The Phantomtrix quickly scans Vilgax's DNA and inputs it into it. While that happens, the Fulmini warriors crash through the walls and starts attacking.
Ben tries to find a useful alien, but then he stumbles upon a new form. Without further questions, he transforms into it. He has transformed into an alien that he titles Gax. Ben complains about the alien looking and smelling like Vilgax, but he admits that he's pretty strong. Ben starts attacking all of the Fulmini warriors, winning in the end.
The two partners get back in the ship and go back home. From now on, Ben doesn't relax because now he knows that there is always evil in the world. Suddenly, an unknown entity enters the universe and visits Earth for his first and only time.