The Best Episodes of Ben 10: Ultimate Alien Season 1

As the team makes its final attempt to stop Aggregor, they find an unexpected ally, and one person will make a fateful decision with lasting repercussions.

Director: Dan Riba

Writer: Joe Casey, Joe Kelly

With the fourth piece of the Map of Infinity almost in Aggregor's clutches, the gang chase him through the artificial planetoid known as Perplexahedron.

Director: Matt Youngberg

Writer: Joe Casey, Joe Kelly

Aggregor has absorbed all the powers of his captured aliens. Now he's after the Map of Infinity.

Director: Matt Youngberg

Writer: Joe Casey, Joe Kelly

Final confrontation with Kevin. While Gwen makes a last ditch effort to save Kevin, Ben fights an all out battle with Kevin.

Director: Dan Riba

Writer: Joe Casey, Joe Kelly

Kevin starts going after Plumbers kids to gain more power. Ben and Gwen continue to argue about how to handle the situation. Gwen tries to find someone who will help her cure Kevin.

Director: Dan Riba

Writer: Charlotte Fullerton, Joe Casey, Joe Kelly

The team encounters another alien who escaped from Aggregor and, through him, learns more about Aggregor's goals.

Director: Butch Lukic

Writer: Charlotte Fullerton, Joe Casey, Joe Kelly

Aggregor has all five aliens. The Plumbers manage to disable Aggregor's ship, forcing Aggregor to find a new way to absorb their powers. The team makes a last ditch effort to save the alien prisoners.

Director: Matt Youngberg

Writer: Joe Casey, Matt Youngberg, Joe Kelly

Aggregor escapes to a magical dimension. Gwen asks for Charmcaster's help to pursue him. The team learns about Charmcaster's past and why she's willing to help them now.

Director: Butch Lukic

Writer: Joe Casey, Joe Kelly

P'Andor, escaped from Aggregor, now wants help to escape his encapsulating suit, but Kevin's the first to perceive that that's a fatally bad idea.

Director: Matt Youngberg

Writer: Marty Isenberg, Joe Casey, Joe Kelly

Ra'ad, the last of Aggregor's escaped prisoners, attacks Ben and informs the team of the true fate of his comrades. He finds a safe hiding place but one that endangers Ben in the process.

Director: Dan Riba

Writer: Len Uhley, Joe Casey, Duncan Rouleau

Argit asks Ben and Gwen for protection from Kevin, so they take him to the nearest Plumbers Academy, but that won't stop Kevin.

Director: Matt Youngberg

Writer: Len Uhley, Joe Casey, Duncan Rouleau

After Jimmy Jones reveals Ben's identity, some of his enemies (such as Zombozo, Rojo, Charmcaster, Vulkanus, and Sevenseven) team up to try to attack his family. Now Ben and his friends have to protect them no matter what.

Director: Matt Youngberg

Writer: Len Wein

Kevin's out for payback on anyone who has ever crossed him. His next stop is a prison in the Null Void. Ben and Gwen try to stop him, where Ben comes to a grim decision.

Director: Butch Lukic

Writer: Joe Casey, Joe Kelly

Then team encounters another of Aggregor's escaped prisoners, Andreas, whom Argit is using as part of a scheme against the Forever Knights.

Director: Dan Riba

Writer: Ernie Altbacker, Joe Casey, Joe Kelly

Ben meets his hero, Captain Nemesis, who's become jealous of all the attention Ben attracts.

Director: Matt Youngberg

Writer: Steven Barnes, Joe Casey, Joe Kelly

Ben's secret is out. As Ben deals with his newfound fame, a new threat emerges as a thief steals parts of a new advanced spaceship from NASA.

Director: Dan Riba

Writer: Dwayne McDuffie

Aggregor is after the next piece of the map on a watery planet.

Director: Dan Riba

Writer: Marty Isenberg, Joe Casey, Joe Kelly

Ben gets an offer to star in his own video game, but the designer's real motives are part of a plan to destroy Ben.

Director: Dan Riba

Writer: Joe Casey, Joe Kelly

Ben is supposed to attend a tournament to support his girlfriend, but the Forever Knights are trying to break into a museum. Ben tries to use the Ultimatrix to handle all his obligations.

Director: Butch Lukic

Writer: Len Uhley

Cash and JT convince the team to allow them to take credit for the team's actions so they can earn money for Cash's mother's operation.

Director: Matt Youngberg

Writer: Peter David, Joe Casey, Joe Kelly