During a battle Ben and an alien commander are teleported to a distant world. They must put their differences aside if they're going to have any chance of finding a way to return to Earth.

Ben, Gwen and Kevin gather their allies to counter the threat of the incoming Highbreed fleet. Azmuth reveals a secret about the Omnitrix.

Ben goes to the HighBreeds' world in an attempt to stop their attack on Earth.

The Omnitrix transports Ben, Gwen, and Kevin to a planet called Primus, which turns out to have been created by Azmuth. They must stop Vilgax from stopping the Omnitrix at its source.

Despite being warned by Paradox, Gwen travels back in time to prevent the accident that turned Kevin into a monster from ever happening. Gwen returns to the present only to find that her time traveling caused a series of events that led to Hex ruling the world.

Ben discovers that the Forever Knights are trading weapons with the DNAliens, while at the same time, Grandpa Max has mysteriously gone missing. He decides to return the Omnitrix on his wrist and go hero once again.

A time experiment in the 1950s sends a bizarre monster to Ben's time. Now Ben, Gwen, and Kevin must team up with Paradox, a time traveling hero, to face off against the unstoppable creature.

Zaw-Veenull asks Ben to deliver Prince Tiffin to Jarret in order to keep peace between the two species. Shortly, after their trip in space, the Omnitrix malfunctions and turns Ben into an Appoplexian named Rath who wants to fight anything that breathes.

Albedo has stolen the Ultimatrix from Azmuth and has used it to kidnap Gwen and Kevin. Ben goes to face Albedo and rescue his friends when he quickly discovers that Albedo has been working in conjunction with Vilgax. Ben is defeated by the pair and gives up the Omnitrix to save himself and his friends.

Powerless, Ben goes aboard Vilgax's ship and faces off with Vilgax to stop his invasion of Earth in their final battle. Albedo gives Ben the Ultimatrix and Ben gets his old aliens and their evolved forms.

Ben, Gwen, and Kevin follow a lead that takes them to a secret base in the desert. There they hope to find Grandpa Max but instead find a Highbreed spaceship with a giant cannon.

Gwen discovers that Grandpa Max's badge is able to signal other Plumbers. However, by using it, they meet up with a familiar face, a pyronite.

Grandpa Max leaves Ben a series of instructions to contact a team of heroes. Things go the wrong direction when they soon find them.

An alien emperor plans to destroy the planet Earth for kidnapping his daughter. In order to save the planet, Ben must uncover the secrets of Alien X.

An alien impersonates Ben with hopes of using his Omnitrix to annihilate him.

Kevin asks Gwen to the school dance; Ben fears he's losing control of the Omnitrix.

An alien named Probity seeks help from Ben to stop the on-going war on her home planet.

A series of earthquakes awakens a HighBreed officer who has been hibernating deep under the earth’s surface. He believes the HighBreed have lost the war and activates a fail safe device that is programmed to destroy. Ben must now work together with Gwen and Kevin not only to save Grandpa Max, but also the world from this "giant" problem.

Vilgax promises Ghostfreak to spring him out of prison as long as he tells him the secrets of the Omnitrix, but when Ghostfreak betrays him and turns his people into his minions, Vilgax comes to Earth and asks for Ben, Gwen and Kevin's help to get rid of Ghostfreak.

Ben, Kevin and Gwen come across an alien box that can forms into a robotic version of whatever it sees. It power becomes a liability when the Vreedle brothers decide to take the box for themselves.

While sick, Ben is visited by old friend Tetrax, who demands that Ben hand over Chromastone.

A new villain comes into town, his name is Darkstar, he commits some crimes and gets the team's attention fast

Cooper is kidnapped by the DNAliens, who want him to build a mystery arch.

To find and destroy the alien dragon species, the Forever Knights capture Ship to control a starship they built out of alien technology to locate their homeworld and destroy them.

A species of goat-like aliens comes to Earth for a popcorn festival. Ben, Gwen, and Kevin have a big problem when one of the aliens eats meat and turns into a monster.