Grudge Match

This is the eighteenth episode of Ben 10.

Plot
The episode starts in the middle of an open field with modern windmills. In the street, Ben's Grandpa Max and cousin Gwen are semi-conscious inside their overturned RV. Ben, as Diamondhead, is fighting Kevin, who's still in his mutated form of combined Omnitrix aliens(from the episode Framed). Before Diamondhead can counterattack, Kevin squirts a greenish fluid(using Stinkfly's ability of slime) to distract him. Kevin carries him up to the air, then drops him, knocking one of the windmills down. Diamondhead responds by throwing the windmill blades at Kevin. Realizing that they match each other's powers, they prepare to attack "normally" by running towards each other. Suddenly, a red beam appears from above, enshrouding them, and they seem to disappear. Gwen and Max get out of the RV, and find Diamondhead missing.

In a dark room, the red beam releases Diamondhead, and a spotlight hits him. As he scans the area, an announcer says the "challenger" comes from planet Earth; it seems that Diamondhead and Kevin have been transported to a fighting arena complete with a variety of alien spectators. While Diamondhead is distracted by his unfamiliar surroundings and situation, a droid attacks him from behind. The droid has two scythes for appendages. Viewed from overhead, the arena is separated in sections, each containing fighters against a similar droid. Diamondhead is able to destroy one scythe, but the droid is strong enough to crack through his crystalline body. Diamondhead realizes that it’s time to become serious, so he slices through the robot’s legs, which seems to disable the machine. As the crowd cheers, it seems that someone has been watching his every move.

Meanwhile, Kevin is in the same situation in an adjacent section, and does the same. He uses different powers to defeat the droid. In a flash, he's victorious, and the crowd cheers for him. It seems that the same person has been watching his every move, as well. As Diamondhead gloats, the Omnitrix times out, and the audience is surprised by the transformation. The damaged droid is able to get on top of Ben, but Ben is fast enough to use one of the detached scythes to severely puncture and terminate the droid. In an holographic projection overhead, the mysterious being who has been watching them announces his plans to use them for subsequent, staged battles for profit. As the wall between Ben and Kevin opens up, Kevin blames Ben for their current situation, but before Kevin can attack the now-defenseless Ben, they are teleported somewhere else.

Kevin and Ben continue to quarrel, but are stopped by hovering robot guards with stun lances. The robots then attach a device to each of them. Ben and Kevin discover that they're on an intergalactic spaceship, in a room with aliens from various planets, who appear to be in the same situation as themselves. Ben insists they should find a way home, but one alien says that the ship is their home, and there's no way out. Still angry at Ben, Kevin grabs him, but the implanted devices create an electrical discharge between them, forcing Kevin off Ben.

An alarm sounds off, and an alien says that it's meal time. The ceilings open and release a gooey, purple-colored substance. Ben doesn’t have the appetite for the alien glop, but the aliens urge him to eat, because "Technorg" will take their food. The sound of heavy footsteps is heard from the background, and a large, orange, alien appears. It's Technorg. As he approaches the aliens, they kneel down to him, while he takes their food. Kevin, still sitting at the table, sneakily uses his "XLR8" tail to throw one of the trays on Technorg’s face, and blames the act on Ben. Technorg grabs Ben, and throws him aside. To match his power, Ben transforms to Four Arms, and returns the attack. Out of view, the mysterious alien continues to watch and be intrigued by Ben’s talents. Four Arms and Kevin are then transported to another area, where the alien identifies himself as "Slix Thigma", who decides to link Four Arms and Kevin using an electronic shackle, telling them that what happens to one of them will happen to the other. Slix then transports them to the arena, where they have to fight Technorg.

As Technorg attacks, Four Arms and Kevin run in opposite directions, forgetting that they're now linked. The mistake allows Technorg to grab a hold of the link and throw both of them down. At that moment, the Omnitrix powers down and Four Arms is returned to his normal self. Kevin tries to get rid of the once again, helpless Ben, forgetting that if Ben is injured or dies, the same will happen to Kevin. Technorg tries an aerial punch, but Kevin's able to dodge the attack. Kevin then runs away from Technorg, dragging Ben on the arena's dirt floor. Kevin continues to humiliate Ben, but Ben attacks Kevin back by tripping Technorg on top of Kevin. Ben insists that if he and Kevin work together, they can defeat Technorg, but Kevin refuses to accept. Instead, Kevin tries to prove that he can win the battle by himself, by alternately shooting Stinkfly's goo and Diamondhead's diamond shards at Technorg, which does virtually nothing to the seemingly indestructible Technorg. As Ben finishes his pleas for Kevin's cooperation, Kevin uses Heatblast’s fireballs, which explosively ignites Stinkfly’s goo. He tells Kevin to try using a combination of powers. It works, with Technorg forced off his feet from the explosions. Ben tells Kevin to use a different combination, and with two powerful punches, Technorg is knocked out. Slix orders Kevin to finish him off, but before he can do so, Ben stops him. Kevin continues to fight with Ben, but are stopped by guards. They are given the title of "Champion", and are taken back to the holding cell.

The imprisoned aliens now pay homage to Kevin and Ben. Technorg appears with a tray of food for Ben, who he's honored to serve, not only because he bested him in battle, but for sparing his life, as well. Ben doesn’t want to be Technorg’s master, and asks if he knows a way off the ship. Technorg says that they've all tried, but it's impossible. As the ship is being prepared to travel to another galaxy, Ben declares that together, they can escape.

A few moments later, as Ben slumps in a corner of the cell, he signals the others to start the plan, and they relay the signal to Kevin who pretends to act out of control. As the robot guards watch, the aliens pile on Kevin, and a flash appears. Grey Matter has managed to sneak inside a robot guard, and disable its control devices. Everyone escapes out of the holding cell. Still linked together, Kevin and Grey Matter try to look for the controls for the emergency escape pods, but Slix is able to track them down, and his drones are well-armed with giant axes. Slix was able to capture the other escapees, and use them as hostages, if they tried to escape again. Kevin and Grey Matter fight the drones to escape and save the aliens from the clutches of Slix, but Grey Matter transforms back into his human self, once again. As the aliens outside are tortured, more robot drones come after Kevin and Ben, who must get to the arena to rescue Technorg from being dropped into a pit of vicious beasts.

Distracted while watching the aliens being tortured, Slix is overcome by Kevin and Ben. Ben insists that Kevin shouldn't destroy Slix, who appears to be an intelligent droid. Kevin, ignoring Ben, is about to destroy Slix, when Ben transforms to Upgrade and merges with Slix. Upgrade explains that the droid is actually the main command center for the entire ship and he can control everything on the ship. He then finds the control console, and breaks their electric shackle link. As Technorg falls from the platform, Upgrade sends a flying platform to catch him. Slix seems able to regain some of his control, but before he can peel Upgrade off, Technorg knocks him out. Upgrade then teleports the imprisoned aliens and themselves to the escape pods.

As Upgrade activates the escape pod doors, every alien escapes successfully, but Technorg insists on staying with Upgrade. Upgrade pushes him into the pod. Just as he's ready to leave, the Omnitrix deactivates, revealing Slix Thigma as a robot, grabbing Ben to destroy him. Kevin destroys Slix, saying that he wanted the fun of hurting Ben, himself. He hurls Ben against a wall, and, using Stinkfly's goo, attaches him there. Ben tries desperately to activate the Omnitrix, and, just in time, he transforms into Cannonbolt. Kevin is surprised by the new-to-him alien form. Cannonbolt bounces off the walls battering Kevin to the floor. He then enters a pod to escape, but Kevin holds the door open, but is stopped by Technorg who's returned to the ship to defend Cannonbolt. Cannonbolt says they're now even, and as he jettisons off the ship in his escape pod, Kevin feigns a meek smile as Technorg approaches, presumably to bash him for his treachery. The ship, having been previously programmed by Slix, disappears into hyperspace, sending Kevin and Technorg far away.

The escape pod lands on Earth, and Ben tumbles out as himself, apparently overcome by the shock of the rocket travel. Gwen and Grandpa have left the damaged RV and seem no worse for wear. They're glad to see that Ben's okay. Gwen asks where Kevin is, and the episode ends with Ben saying that Kevin's found someone new to play with, and that they probably won’t be seeing him for a while.

Characters

 * Ben (Main Character in this episode)
 * Kevin 11 (Main Character in this episode)
 * Gwen
 * Grandpa Max
 * Technorg
 * Slix Vigma

Aliens used

 * Diamondhead
 * Four Arms
 * Grey Matter
 * Upgrade
 * Cannonbolt

Trivia

 * Some of the aliens on the Omnitrix appear in crowd scenes throughout the episode.
 * Animation mess-up: After Ben stopped Kevin from killing Technorg and they're being restrained by the guard-bots, Ben's Omnitrix is on his right hand.
 * "Grudge Match" is also the name of a similar Justice League Unlimited episode; where the main characters are also kidnapped (Huntress, Black Canary, Wonder Woman... ; Ben and Kevin) by a fight enthusiast (Technorg; Roulette), they are forced to fight for their lives, and they all work together to get out of the competition.
 * Kevin fired Stinkfly's goo at Ben's back, but when Ben was pinned to the wall, he was facing Kevin.
 * When Four Arms and Kevin get thrown by Technorg, when they land, Four Arms has five fingers instead of four.

Quotes:

 * (Kevin has Ben trapped on a wall; Ben's trying to activate the Omnitrix)
 * Kevin: Don't bother trying to dial in another alien. I know all your aliens powers inside and out.(starts to attack him)
 * (Ben slams the Omnitrix on the wall, the attack shatters; Cannonbolt looks up at Kevin, who takes a step back in surprise)
 * Cannonbolt: Oh, yeah? I don't think you've been introduced to Cannonbolt! (jumps off the wall and attacks him)


 * Kevin: (in his combined alien form) You are one sorry sight, rock head.
 * Diamondhead: That's Diamondhead, and speaking of sorry sights, have you looked in the mirror lately?
 * Kevin: It's payback time for turning me into a freak.
 * Diamondhead: You were always a freak, Kevin. It's just now the ugly is also on the outside.


 * Kevin: (in his combined alien form; to Ben) Diss me all you want. I'm still 10 times better than you! I've got all your powers, plus my own! I'm Kevin 11! (attacks him)
 * Diamondhead: (blocks attack) Too bad each one of those are only a tenth as powerful as mine!