Aggregor

Aggregor is an artificial Osmosian intergalactic criminal whose main objective was to get to the Forge of Creation and absorb the powers of an infant Celestialsapien (which he refers to as the "Ultimate Prize") to gain unlimited power and rule the universe. Ruthless and cunning Aggregor was dangerous enemy for Ben, as well one of his most dangerous enemies.

To achieve this goal, he absorbed five powerful aliens he hunted down from the Andromeda Galaxy.

Appearance
Aggregor's appearance is similar to that of a human. However, he has small flesh-colored horns on his head and red eyes ringed with black marks (a sign of recent Osmosian energy intake). He has long, black hair. He wears a brown knee-length, open-chested tunic, baggy jeans, black calf-high boots, and wields a spear-like weapon that he can use to fire red energy projectiles.

Personality
Aggregor is a cruel, sadistic, menacing and remorseless sociopath, who does whatever it takes to achieve his goals, having no remorse for any of his actions. His intelligence is extremely high and his plans go to very great lengths to succeed. Aggregor's abilities make him a very formidable enemy and he has managed to hold his own against even the Plumbers. He fears no one and hungers for power.

Unlike most of Ben's other enemies, such as Vilgax and the Highbreed, Aggregor prefers to carry out his plans himself instead of trusting his robotic minions to do the work, instead using them for lesser duties, such as maintenance, manual labor, security, and being cannon fodder against his enemies. He had captured and recaptured all of the five Andromeda aliens by himself.

Additionally, Aggregor's hunger for power appears to stem from the possibility of not wanting to be weak. His rebuttal to Kevin's claim that absorbing energy causes Osmoians such as himself to go insane, "Lies! Told by the powerful to control the weak!". This also relates to desire to possess ultimate power in order to control the entire universe.

Background
Sometime after Kevin and the Amalgam Kids failed to capture Ben Tennyson, Servantis created Aggregor as a lab experiment. Servantis used Kevin's DNA to create a perfect copy of Kevin's absorption powers. Just like the other prisoners of Servantis, he was taught about aliens and their powers. However, after Ben removed the Omnitrix, Servantis wiped his mind and set Aggregor loose as well, since there was no need for an army anymore.

Ultimate Alien
In Fame, after Bivalvan was defeated, he explains that Aggregor captured him along with four others but they managed to escape to Earth. At the end of the episode, instead of the Plumbers who Bivalvan was expecting to send him back to his home planet, Aggregor appeared. His first line was "No one escapes me, Bivalvan" and he captured him.

In Escape from Aggregor, Galapagus told the tale of how he and the other four aliens were captured and escaped. Aggregor revealed that his plan was to absorb all the powers and abilities of the five aliens he captured using a machine he had built back on Osmos V in order to become strong enough to gather and reassemble the four pieces of the Map of Infinity so he can travel to the Forge of Creation and absorb the powers and abilities of a newborn Celestialsapien so that he can become omnipotent (which he refers to as "The Ultimate Prize"). At the end of the episode when Ben sent Galapagus back to Aldabra, the Plumber that was transporting him is revealed to be Aggregor in disguise.

In Too Hot to Handle, after Ben, Gwen and Kevin succeeded in subduing P'andor and had him sent home. Aggregor attacked the ship transporting him. Aggregor's attack resulted in the Plumbers being flung into space, killing them, while he recaptured P'andor.

In Andreas' Fault, Aggregor found Andreas buried underneath the remains of a Forever Knight castle before transporting him back to his ship and putting him in a stasis pod alongside Bivalvan, Galapagus, and P'andor, with only Ra'ad remaining to be recaptured, after which he states that then "the fun begins".

In Fused, Ben, Gwen and Kevin met Aggregor face to face. It was revealed by Ra'ad that Aggregor was using the signal of the Ultimatrix to locate the aliens. Ra'ad attempted to destroy the Ultimatrix to prevent Aggregor from finding him, but the Ultimatrix attempted to scan his DNA at the same time, resulting in Ra'ad being trapped in the Ultimatrix and AmpFibian was the only alien Ben could turn into. When Aggregor arrived and defeated Kevin, Ben transformed into AmpFibian. Aggregor attempted to use AmpFibian as a replacement for Ra'ad, but Gwen used a teleportation spell to teleport herself, Kevin and AmpFibian to Kevin's warehouse. Aggregor returned to his ship to have his sensors track the Ultimatrix signal, but it was off-line because of Ra'ad's attack. Gwen and Kevin rebooted the Ultimatrix to separate Ben and Ra'ad, allowing Aggregor to find them again. Knowing he would be coming, Ra'ad quickly fled just as Aggregor came in through the roof again. After dispatching Kevin and Gwen, Ben confronted him as Brainstorm. Unfortunately, Aggregor used his spear to ground Brainstorm's lightning attacks and neutralized his electrokinetic powers with the red energy blast from his weapon (nearly killing him in the process). He then attempted to change Brainstorm into AmpFibian for his plan by stabbing and manipulating the Ultimatrix with the blade of his spear. However, Ra'ad (having been given a lecture by Kevin) returned to save Brainstorm. In the clash between Ra'ad's lightning attacks and the red energy blast of Aggregor's spear, the warehouse exploded, but Ben and Gwen were able to escape while Aggregor captured Ra'ad during the blast. With all five of his prisoners recaptured, Kevin feels Aggregor has won, but Ben, having scanned all five aliens, vows to use their powers to stop Aggregor.

In Ultimate Aggregor, it was shown that after Aggregor escaped the warehouse's explosion with Ra'ad, he traveled out into the desert to call his ship and transport him. However, he found himself ambushed by the Plumbers. Unfortunately, Aggregor was prepared and unleashed a torrent of laser cannons to bring down the entire ambush while he transported himself and Ra'ad to his ship. Just as he was about to make a jump to Osmos V, the lead Plumber of the ambush used one of the downed ships to take out the hyperdrive of Aggregor's ship. Unable to leave Earth, Aggregor had to come up with a new plan. When Ben and his team tracked his ship, they were attacked by Aggregor's robots. When Lodestar boarded the ship, it self destructed. Fortunately, Lodestar was able to survive with his magnetic abilities pulling him back together. Meanwhile, Aggregor broke into Los Soledad with intent on using the Entropy Pump from Paradox's old time-traveling experiment as a replacement for the machine on Osmos V. Upon discovering where he was, Ultimate Swampfire and his group stormed Los Soledad, charging through the remainder of Aggregor's robots. Needing more time, Aggregor used a mind control device to have the five Andromeda aliens attack them. Upon being freed from his control, Aggregor recalled the aliens. When Nanomech and his team confronted Aggregor, Kevin warned Aggregor not to go through with his plan, mentioning that absorbing energy causes Osmosians to go insane, explaining Kevin's acts in the original series. Aggregor however, refuses to believe it, claiming that powerful Osmosians told that to weak Osmosians to control them. Before Kevin could convince him otherwise, Aggregor used the Entropy Pump to transfer the powers and abilities of the five aliens into himself. Humungousaur managed to stop the pump before it destroyed reality. Unfortunately, it was too late as Aggregor had completely absorbed the five aliens, transforming into his mutated state, a massive chimeric mutant, named Ultimate Aggregor.



In The Forge of Creation, Ultimate Kevin attacks Ultimate Aggregor and absorbs him, reverting Ultimate Aggregor back to Aggregor and leaving him unconscious. Though Ultimate Kevin, gone insane from absorbing the Ultimatrix energy, was about to kill him, he is persuaded to spare his life by Gwen, Ben and Young Ben.

Aggregor was taken into custody by the Plumbers. Later, Aggregor was sent to the Null Void.

Powers and Abilities
Being an Osmosian, Aggregor has the ability to absorb matter or energy from anything in order to use it in various ways. He prefers absorbing powers from other lifeforms, acquiring 1/10 of the creature's powers.

Unlike Kevin (until he used the machine), the powers and abilities Aggregor absorbs don't change his appearance (when Aggregor absorbed a Geochelone Aerio, his appearance stayed the same, though he could now open six holes on his torso at will to make use of the species' abilities). Also, while Kevin, when he absorbed powers from the Omnitrix aliens, left them unharmed (as he absorbed the transformative energy of the Omnitrix rather than the aliens' themselves), Aggregor absorbs all of his victims' energy, leaving behind nothing but a desiccated skeleton/shell. An exception goes with the machine he used that boosted this ability and allowed him to absorb the aliens' bodies as well.

Equipment
In addition to his absorbing powers, Aggregor has a spear-like weapon that can fire blasts of red energy that can disrupt other energy fields or attack. He can use his spear-like weapon to summon his ship as well as lift objects with an electromagnetic aura that is the same/similar energy from his spear. According to him, his spear is designed to combat electromanipulative species, as seen when he used it to redirect Brainstorm's electrical attacks.

Much like Vilgax, Aggregor has an army of Aggrebots at his disposal rather than living soldiers, though his robots are more humanoid in shape and stature than Vilgax's.

Weaknesses
Aggregor was very dependent on his spear.

Aggregor was vulnerable to Gwen's mana attacks.

Without his spear, Aggregor is vulnerable to energy-based attacks unless he were to use his natural absorption powers to absorb them. However, he lacks experience with absorbing energy, and doing so could be potentially dangerous to his physical and mental state.

Ben could've defeated Aggregor in Fused, if he hadn't used an electrokinetic alien.

Ben 10: Ultimate Alien

 * Fame (first appearance)
 * Escape from Aggregor (flashback and present)
 * Too Hot to Handle
 * Andreas' Fault
 * Fused
 * Ultimate Aggregor
 * The Forge of Creation (cameo)
 * Night of the Living Nightmare (dream)
 * The Ultimate Enemy: Part 2 (flashback; cameo)

Cartoon Network Action Packs

 * Ben 10 On Ice
 * twoSome

Etymology
Aggregor's name comes from the word "aggregate", which means to form a collection from different parts. This is obviously a reference to his plan to absorb the five aliens' powers which re-created his body using the parts from the Andromeda aliens.

Trivia

 * Aggregor was a much greater threat than Vilgax, even before he became Ultimate Aggregor.
 * Kevin has more experience with absorbing energy than Aggregor.
 * Aggregor knows about the Forge of Creation through him studying legends for his entire life.
 * Aggregor didn't place the Andromeda Galaxy aliens in the separate pods in Escape from Aggregor because he wanted to save power.
 * Aggregor refers to Kevin, a fellow Osmosian, as a "hatchling," a reference to their difference in age and power.
 * However, this was due to the false memory implanted by Servantis, as Aggregor's powers itself came from Kevin.
 * Aggregor is one of the few villains that was never beaten by Ben himself.
 * In his first appearance, Aggregor had six horns; In all his other appearances, he had only four.
 * It was originally planned that the Rooters arc would begin by having Aggregor seek out Kevin, revealing that he was an experiment by the Rooters to duplicate Kevin's powers.
 * If that episode was to go as planned, Aggregor's genetic code would have been breaking down resulting in his "death" having been melted into what Derrick called "ooze".
 * Aggregor is mentioned in Cosmic Destruction by Psyphon, who says that he considered working for Aggregor, but he preferred to work alone. Also in the same cutscene Psyphon said: "and look where it got him".
 * Aggregor's Toon Cricket Team's name is Aggregor Aggressives.
 * Aggregor's appearance is very similar to a Zabrak (more specifically Eeth Koth, Agen Kolar, Savage Oppress, and Darth Maul) from Star Wars.
 * And his personality is similar to Ganondorf from "The Legend of Zelda" series, with the two studying legends of an infinite power and hunt this infinite power to govern his universe.