Alien X

Alien X is a Celestialsapien who are born in The Forge of Creation and exsist on the planet Zvezda. He is an Omnitrix alien that appears in the show Ben 10: Alien Force and Ben 10: Ultimate Alien.

Biography
Ben acknowledges Alien X as his most powerful alien; however, he cannot afford the cost that comes with becoming the alien. Alien X is a being capable of warping reality at will. He has a black body covered with tiny white stars, white hands, green eyes, and three horns protruding from his head. He has three distinct personalities: Serena, the voice of love and compassion; Bellicus, the voice of rage and aggression; and Ben, the voice of reason. All three speak in unison when Alien X speaks. In order for Alien X to perform any action, including but not limited to, simple movement and transforming back into Ben, two of the three personalities must agree to do so. As both Serena and Bellicus have been arguing for an eternity, and before Ben had no tiebreaker, getting them to focus on any present task is difficult at best, leaving the body of Alien X frozen in place while Ben attempts to convince them to act.

Alien Force
Alien X first appears in X = Ben + 2, where Ben uses the form to stop a flood caused by a broken dam. After much fruitless argument, Ben eventually convinces them to transform him into one of his other nine aliens. He swears off using the form afterward, as it isn't worth the price the power comes at.

Ultimate Alien
Alien X appeared in the episode "The Forge Of Creation" to stop Aggregor from obtaining Alien X's powers. Except Bellicus and Serene keep fighting and Paradox tells him not to be him at this time.

Abilities
He possesses vast reality warping powers, meaning he can make his thoughts become reality, alter matter, control living things, actions and thoughts, manipulate time, have the powers and appearance he wants, and (as confirmed by Bellicus in X = Ben + 2 when he states that Ben will never change back) stay in this form as long as he wants. He is also the strongest and most powerful alien that Ben knows about, but may not be the most powerful in the Omnitrix/Ultimatrix.

Weaknesses
In order for Alien X to perform any action, including but not limited to, simple movement and transforming back into Ben, at least two of the three personalities(Serena, Bellicus, or Ben) must agree to do so. This reveals to be a major weakness, as the personalities initially weren't even interested in dealing with present affairs and wanted to finish some past ones that weren't possible to deal with without Ben (with a comical scene where Bellicus reopens a discussion on whether or not to save dinosaurs from extinction).

Alien Force

 * X = Ben + 2

Ultimate Alien

 *  Forge of Creation (episode)

Alien Force

 * 4" Alien X
 * Alien X (Planetary Powder)
 * Alien X (Alien Creatures set)
 * 10 cm Alien X (DNA Alien)
 * Alien X with Goop (Black version) (Creation Transporter)
 * Alien X (Defender) with Alien Bust
 * Alien X (Alien Creation Launchers)
 * Omnitrix Hero Collection with Alien X hologram
 * Alien X (Alien Rocks)
 * Alien X (Keychain)

Ultimate Alien
Alien Creation Alien X and Ben

Ben 10 Alien Force: Vilgax Attacks
Alien X appeared in the game (only in the CGI movies/clips for X-Box 360, Wii, PS2 and PSP). He is not a playable alien being replaced by Cannonbolt/Upchuck.

Trivia

 * He has only been used once, in X = Ben + 2, and The Forge of Creation making him the second least used alien (tied with Benmummy used once in The Return and Ken 10) beating Benvicktor and Benwolf which have only been used once.
 * Alien X has a white shadow.
 * Alien X also cannot be destroyed if all voices disagree on being destroyed and state "Motion denied".
 * Alien X is Ben's most powerful alien, but it is also his most risky to use. The extent of his power is unknown.
 * Before he appeared, the opening showed only a shadow of him, after he did it showed a normal image.
 * The X in his name is probably used to signify him being the 10th alien by the Roman Numeral 10. It may also relate to his mysterious nature, as X is often used in Mathematics to represent an unknown number.
 * At the beginning of the video game Vilgax Attacks, Ben starts to turn into Alien X. But Paradox tells him not to yet, but later in the game there is a cutscene where he sends Vilgax and Psyphon to the Null Void. In the DS version, after being defeated by Ben, Albedo turns into Alien X but is frozen and cannot do anything. After the credits in the last level, we see a cutscene where Albedo is still frozen in Alien X.
 * Due to the fact that Alien X was on the spoiler poster, and seen on the prototype Ultimatrix alien designs, it is known that he will be in Ben 10: Ultimate Alien.


 * He is also becoming a "Nano" and a NPC in Cartoon Network Universe: Fusion Fall.
 * Bellicus's name is probably based on the word bellicose, meaning aggressive or eager to fight, while Serena's name is probably based off the word serene, meaning calm or peaceful, both references to their personalities.
 * Alien X appears to be entirely made up of space itself, hence the stars all over his body.
 * Alien X is one of the five alien forms that shares the same voice actor as its human form. The other four being Upgrade, Benwolf, Buzzshock, and AmpFibian (only in episode Fused).


 * Alien X is one of the nine aliens to appear on a limited edition smoothy cups in Andreas’ Fault.
 * Alien X is Ben's 30th alien, and it's the 10th alien of Ben 10: Alien Force.
 * Through Alien Force, Kevin tries to get Ben to use Alien X even though he knows all about the risks of using him.
 * In Andreas’ Fault, a devoted fan of Ben's refers the "Alien X" smoothie as a disappointment as well as calling it "filler". This is an obvious reference to Alien X's standing in the series.
 * The three horns on Alien X's head could represent the three personalities that control Alien X.
 * Alien X is so far the only alien with 5 fingers.
 * In X = Ben + 2 Ben did an action was first then had to argue. But in The Forge of Creation he didn't do any action.
 * Is able to fly according to The Forge of Creation.
 * Ben had Kevin rig the Ultimatrix with an extra lock, preventing anyone from accessing Alien X with out first inserting two keys. This was done to prevent people with bad intentions from using Alien X and to keep Ben from using it should he get to tempted.
 * The block set on the Ultimatrix that prevents the use of Alien X appeared to have been reactivated after Professor Paradox transformed Alien X back to Ben, for when Kevin absorbs the powers of the Ultimatrix later in the episode to save their lives, he did not recieve the abilities of Alien X.
 * Alen X is the second alien to be shown as a baby, the first being BigChill
 * In Forge of Creation, Paradox somehow turns Alien X back into Ben.