Alien X is the Omnitrix's DNA sample of a Celestialsapien from the Forge of Creation.
Alien X has three personalities: Serena, the 'voice of love and compassion', Bellicus, the 'voice of rage and aggression' and Ben, the 'voice of reason'. All three of these voices combine to form Alien X's speech. Otherwise, Alien X is silent. The only things he will say are what he will be doing - what Ben, Bellicus and Serena have agreed to do.
As Serena and Bellicus have been arguing for eternity and before they had no tiebreaker, getting them to focus on any present task is difficult at best. This leaves Alien X's body trapped in place, floating about a foot above the ground until an agreement is made.
Alien X is a humanoid alien whose entire body is solid black, excluding his hands, which are white. He has tiny white star-like spots all over his body, giving him the appearance of a starry night sky. His eyes are green and lack pupils, and his forehead bears three horn-like protrusions. Later in the series it is implied that his starred body isn't simply 'aesthetic', but that Alien X, and by extension all Celestialsapiens are, or contain their own 'pocket universes', as Paradox was able to travel inside Alien X and speak to Ben whilst he was arguing with Serena and Bellicus before reversing the transformation.
In Omniverse, Alien X is largely the same as before, but with minor changes. His chin is now bigger, his body is more muscular, his horns are smaller, and the stars on his body are brighter than before.
Alien X wears the Original Omnitrix/Ultimatrix/Omnitrix symbol on his chest.
Powers and Abilities
- Alien X is omnipotent.He can do anything.
He is clearly invulnerable to everything(except Anur Vladias). Though, he can make himself invulnerable to Anur Vladias by agreement with the personalities.
In order for Alien X to perform any action, including simple movement and transforming back, all three of his personalities must agree to do so. This has proven to be a major weakness, as Serena and Bellicus weren't interested in dealing with present affairs and wanted to finish past ones that weren't possible to deal with without Ben. Though, this is not a problem anymore because the personalities gave Ben full control over Alien X. So Ben can do anything by Alien X without agreeing of the personalities.
In Ben 10,000 Returns, the said weakness was referenced by Professor Paradox, where he revealed that there is an alternate timelinewhere Albedo transformed into Negative Alien X and was stuck motionless for nearly a year.
Alien X is vulnerable to having his powers absorbed, as Ben and Azmuth have implied that Darkstar and Osmosians can absorb his omnipotent powers. This was in factAggregor's master plan - he collected the powers of 5 aliens (Galapagus, Bivalvan,Andreas, Ra'ad, P'andor) from the Andromeda galaxy to gain access to the Map of Infinity, in order to gain access to the Forge of Creationso he could absorb the powers of a newborn Celestialsapien. Though, he can make himself invulnerable to power absorption.
Other Celestialsapiens and omnipotent beings can harm Alien X, as shown in Universe vs. Tennyson.
According to Derrick J. Wyatt, even Alien X can't survive on Anur Vladias.However he can make himself invulnerable to Anur Vladias by agreement with the personalities.