Deep

Deep is the thirteenth episode of Ben 10: Ultimate Alien.

Plot
Underwater, a Magister Plumber of the Piscciss Volann named Pyke (Ripjaws' species) is searching for something. He finds a swimming object which happens to be Ultimate Aggregor who seems to have defeated Pyke.

Ben is being surrounded by fans and tries to escape as Goop, but Gwen and Kevin pick him up and save him. Ben receives a message from Pyke on his Ultimatrix about Ultimate Aggregor. They take Kevin's jet to go to Pisciss (Ripjaws' homeworld) to search for Pyke, but are attacked by a monster. They use the electrical gauntlets in their Plumber suits to defeat the monster, but in the battle Kevin's helmet cracks.

With Kevin dying, Gwen gets him absorbing his jet's coating, while a nearby fish is able to convert itself into a helmet for him. Pyke shows up and the kids go with him to find Ultimate Aggregor. Ben's helmet cracks when they battle many sea creatures, and he tries to transform into an underwater alien to stay alive, but becomes Humongousaur instead. With a few moments to live, Ben becomes AmpFibian. They pass the guards once they explain their Plumber business, and go to the core of the planet, where it looks like Ultimate Aggregor is attacking. The core is able to have air in it, and Pyke uses a water helmet to breathe. But a tremor occurs and Pyke is crushed by a rock. While Gwen stays to help him, Ben and Kevin go on, but find Ultimate Aggregor grabbing the planet's core piece that keeps it together.



It turns out the core piece is the second piece of the Map of Infinity, which Paradox did to cleverly disguise it so Aggregor would not suspect. Ultimate Aggregor leaves the core. Ben becomes Big Chill and chases Ultimate Aggregor. Gwen, Kevin, and Pyke have to deal with the core guards. Ben becomes Ultimate Big Chill when the guards keep confusing Ben and his friends as the culprits for stealing the core piece. Ultimate Aggregor, unfortunately, escapes with the piece. Ben, trying to prevent the planet from scattering into pieces, transforms into Goop again, and uses his antigravity device as a substitute, but it also sucks in Goop's body. Soon the planet's surface glows green (Goop's color) and the planet pulls itself back together, with Ben transforming back to himself and being saved by his friends before he drowns. Pyke thanks the kids for their help and Kevin wards off the fish that was used as his breathing helmet earlier (who grew a soft spot for him). They leave and now there are only two pieces of the Map of Infinity Ultimate Aggregor has yet to claim.

Characters

 * Ben
 * Gwen
 * Kevin
 * Magister Pyke
 * Little Fish (friend of Kevin)
 * Piscciss Volann Core Guards

Villains

 * Ultimate Agreggor
 * Fish Guardians

Aliens Used

 * Goop (x2)
 * Humungousaur
 * AmpFibian
 * Big Chill
 * Ultimate Big Chill

Names in other Languages
Spanish (Latin America): El Nucleo (The Core)

Errors

 * When Magister Pyke get his helmet, Kevin is not in the green armor two times.
 * When Ben as Big Chill is flying after Aggregor, when the two Pisciss Volannuses start to chasing him, for a moment it can be seen that the one on the left is wearing a Plumbers' suit, not the usual guard uniform.

Trivia
This is because we do not know what type of material the Rustbucket is made of; it maybe a very lightweight metal
 * In Fused, Amperi kind (Ra'ad), can NOT stay in water, but here, AmpFibian can. The reason he couldn't be in water in Fused was because he had an electrical charge on him and the pool had chlorine in it.
 * In Ben 10 Alien Force episode "Everyone talks about the Weather" Kevin said he didn't have a cell phone but in this episode Kevin said he took pictures of Ben being attacked by fans on his phone, this must mean he bought a phone.
 * This is the third time that Ben goes alien to get away from adoring fans. But unlike the first two times, this time the plan backfires.
 * Ripjaws was mentioned in this episode when Ben sees the cool stuff Magister Pyke (who is also a Piscciss Volann like Ripjaws) does; he asks how come he could never do that as Ripjaws.
 * So far since Ultimate Aggregor, everytime they see Aggregor, somebody yells out his name.
 * When Kevin absorbed the Rustbucket, he should have sunk, but instead he continued to float as easily as Ben and Gwen.
 * This is the second time Ben has to stay an alien so he can survive. The first time is in Map of Infinity.
 * When Goop was repairing the planet, Pyke was seen breathing easily despite the lack of water. Likely because he's older and he still was hydrated. It was later confirmed that he could breathe the whole time "just not as easily"
 * Big Chill/Ultimate Big Chill can breathe underwater.
 * This is the first episode that Kevin absorbs a single type of matter.
 * This is the first episode in which we saw AmpFibian with green eyes.
 * In this episode, Ben almost died of not breathing underwater, but transforming into AmpFibian saved his life.
 * When Aggregor tells kevin next time absorb something that doesn't conduct electricity Kevin uses this advice.
 * Dwayne McDuffie confirmed that in this episode, Ben scanned a Piscciss Volann which allowed him to get Ripjaws again.
 * This episode airs in the UK on the 9th February 2011.
 * This episode airs in Latin America on the 6th March 2011.