Ben Again

Ben Again is the eighteenth episode of Ben 10: Omniverse.

Plot
The episode begins with young Ben as XLR8 battling Eon for the first time. Then teen Ben as Diamondhead is shown battling Eon as well. Just then when both Ben's Omnitrix time out, both Eons grabbed the Omnitrixes, causing an explosion. When teen Ben awakes, he's in young Ben's body, but doesn't notice and thinks his Omnitrix changed to look like his old Omnitrix. So Ben transforms into Ditto and fought Eon, but Eon disappears and the Dittos think they pummeled Eon into oblivion. But when Gwen and Grandpa Max arrive, Ben turns back to normal and is shocked that Gwen's younger and he is too. Ben tries to tell them that he's a teenager and that Eon brought him here, and Gwen and Max do wonder why Ben's voice is different. So they ask Ben where young Ben is, then it shows young Ben in teen Ben's body, which young Ben loves. Rook and Max also wonder why their Ben's voice is different. Just then, Eon appears and Ben is about to fight. He notices the new Omnitrix and all the aliens, saying that this is the best day ever. When Eon mentions Professor Paradox, Ben is confused and Eon remembers that young Ben hasn't meet him yet and realizes Paradox would have to go to teen Ben. Back in the past, Gwen asks Ben what's she like and Ben says he misses her making Gwen think she's dead, but Ben corrects her, saying that she just goes to college early. Max tells Ben he should stop telling them about the future. Suddenly, Paradox appears with a lot more features on his clothes and says it's because of a time war. Max and Gwen are confused and Paradox introduces himself, with Paradox bringing Ben with him to talk in private. Paradox tells Ben that Eon wants nothing less than absolute power over everything.

Paradox tells Ben he trapped Eon in this timeline and that he can only travel to the past, present, and future. He also says the key to get out is with Paradox's pocketwatch, which is like a GPS for the multiverse. Eon reappears and Paradox and Eon get in a fight, which results in Eon cutting off Paradox's robotic hand. Before Eon and Paradox leave, Paradox gives Ben a clue as to where his Chrono Navigator is, and Ben realizes its his robotic hand, because Paradox used the words "well in hand". Ben ponders what to do, weirding Gwen out because of how much more mature he is compared to his younger self. He then comes up with an idea, making Gwen promise to find him no matter where he is in EXACTLY five years from now; he then leaves with the robot hand to hide it. At Plumber headquarters, young Ben is being mischievous, and Rook wonders if there's someone who has experience with young Ben. Then, someone says that she does, which is revealed to be Gwen. She asks if Ben is mentally an 11- year old, and Ben examines Gwen, saying that she's still a dweeb. Rook asks why Gwen's here, and she explains the promise teen Ben made her keep. Ben says it wasn't him and Max wonders if his 16 year old mind got sent back to his 11 year old body, which he calls a cross time brain swap. Rook asks if she recalls anything else, to which Gwen replies she has to take Ben to Mr. Smoothy's, to which Ben replies that smoothies are gross. However, Rook points out that teen Ben loves smoothies, something that confuses the younger Ben.

Then Gwen tells Ben that in the future, Mr. Smoothy is where she, him, and Kevin used to hang out. This makes Ben wonder who "Kevin" is, only to be shocked to find out that it's Kevin Levin. Gwen tries to explain that Kevin changed and became a good guy, but her tone immediately makes the younger Ben realize she's dating Kevin; he finds this to be way more gross than smoothies. Examining their surroundings, Rook points out that there is a Sumo Slammer sticker on a pole. Gwen says Ben should look at the top of the pole, so Ben turns into Diamondhead and sees some coordinates, with the name Armodrillo scribbled. Then they follow the coordinates and reach Pakmar's new place. Armodrillo digs into a specific point (as per the coordinates) and finds another no written down there, but accidentally hits a pipeline and the trio run away, with Pakmar's place flooding. Then, Ben turns into different aliens to find hidden coordinates (Goop to see in a tap, NRG to go into hot reactors, and Wildmutt to search the ground and dig.) They finally come back to Mr. Smoothy's and Gwen asks Ben why he would do all that clue searching to just come back where you started. Ben replies, saying that nobody would look for the treasure if the treasure is hidden at the place that you started with, which Gwen agrees to, as it was a clever plan. Ben turns into Big Chill, and gets the Chrono Navigator from the Mr. Smoothy's vendor. Then he tries to check (acts like shooting and then backscratches) what it is when Eon comes and takes it.

Eon explains that what the dimwitted Ben had is the key to the multi-verse, summoning his minions to fight. However, as they're defeated and Eon continues to call more, the portal they came out of did not close. A portal then appears in the present, and the past and current Ben and Gwens can see each other. Teen Ben turns into Wildvine to reach into the past to take the Chrono Navigator from Eon, but is repelled. Paradox appears in another portal, berating Eon for not listening to him about the dangers of messing with space and time. Gwen tells her younger self a spell that can free Paradox from his imprisonment. Both cast the spell and succeeded in freeing the professor, who promptly tells both Bens to turn into Clockwork to trap Eon between both points in time to restore order to the universe. However, teen Ben points out Clockwork is not available in the prototype Omnitrix. Paradox counters by explaining that both Omnitrixes are synced to each other now thanks to Eon's bumbling, allowing the prototype to access the DNA needed for the transformation. Both Bens turn into Clockwork and blast Eon from both points in time. Young Ben quickly deduces their memories of the event and the event itself will be erased immediately.

Time is restored to normal, with teen Ben and Rook enjoying smoothies outside Mr. Smoothy's. Ben is bored, hoping for some universal calamity; Rook agrees, hoping something interesting will happen. At that very moment, Ben 10,000 arrives through a green portal, asking teen Ben for Paradox's location. He informs his younger self that the Chronosapiens had gone rogue and Maltruant's temporal beasts are on a cross-dimensional rampage, saying that this time war is getting out of hand.

Teen Ben is delighted to hear about a Time War, finding the idea awesome.

Major Events

 * Ditto and Wildvine (for 11-year old Ben) make their Omniverse debuts.
 * Professor Paradox, Eon and Ben 10,000 make their Omniverse debuts.
 * Clockwork is temporarily unlocked for 11 year old Ben.

Characters

 * Ben Tennyson (11 and 16 years old)
 * Rook Blonko
 * Gwen Tennyson (11 and 16 years old)
 * Max Tennyson (61 and 66 years old)
 * Professor Paradox (first re-appearance)
 * Plumbers
 * Blukic
 * Driba
 * Jerry (cameo)
 * Molly Gunther (cameo)
 * Pakmar
 * Ben 10,000 (first re-appearance)

Villains

 * Eon (first re-appearance)
 * Eon's Servants (first re-appearance)

By 16 year old Ben

 * Diamondhead
 * Ditto (first re-appearance; in 11 year old's body)
 * Wildvine (in 11 year old's body)
 * Clockwork (in 11 year old's body)

By 11 year old Ben

 * XLR8 (off-screen transformation)
 * Diamondhead (in 16 year old's body)
 * Armodrillo (in 16 year old's body)
 * Goop (cameo; in 16 year old's body)
 * NRG (cameo; in 16 year old's body)
 * Wildmutt (in 16 year old's body)
 * Big Chill (intended alien was Armodrillo; cameo; in 16 year old's body)
 * Arctiguana (in 16 year old's body)
 * Clockwork (in 16 year old's body)

Spells Used

 * Combibo Potentia

Allusions

 * Doctor Who is homaged by Paradox mentioning being a part in a time war, this is explained by the Doctor as the reason the Time Lords aren't around anymore in Doctor Who. This is further expanded upon in David Tennant's last episode The End of Time.
 * The Chrono Navigator's former and current shape reference The Doctor's fob watch (a part of the chameleon arch) and Rassilon's gauntlet respectively, the later further referencing The End of Time.
 * When Ben says "Abso-tively poso-lutely", this is what Dodger from Oliver &amp; Company says for most parts of the film.

Trivia

 * This episode replaced the episode Tummy Trouble due to a change in the schedule.
 * Due to Eon being defeated, the time-stream reset from the beginning of the episode causing the events in this episode to never have happened, except for the part at the end where Ben 10,000 came looking for Professor Paradox.
 * According to Matt Wayne, despite Ben 10,000's appearance it is not necessarily his real future.