Ben 10,000 has become a full-time hero. He is tall, more muscular, and sports a full-beard. The Omnitrix has also changed in appearance, becoming bulkier and more gauntlet-like in shape. He is recognized everywhere as Ben 10,000, no matter what alien form he is using (because his aliens have an Omnitrix symbol).
His nickname comes from the fact that now Ben has access to at least 10,000 alien forms (he says he stopped counting), he also has unlocked the Omnitrix's Master Control, allowing Ben 10,000 to switch forms at will, without timing out.
Having been fighting crime for such a long time, Ben 10,000 has grown into a strict and serious character, stopping naming his aliens (which the present Ben considers "half the fun" of using them), and has a darker way of dealing with villains, such as defeating Vilgax by literally mutilating him (according to a pop-up, this happened when Ben 10,000 was 15), though his interaction with his younger self causes him to lighten up somewhat, renaming his aliens. Ben's alien forms have aged with him, which is evident in their appearances and abilities. For example, Ben 10,000's XLR8 is noticeably taller with gray outlines in place of the ordinary blue, as well as being considerably faster.
It was shown that Ben 10,000 has a son named Kenny (after Ben's cousin Ken) and a daughter named Gwendolyn(after Gwen). On Kenny's tenth birthday he gives him an Omnitrix like the one he had in the original series (like his first one, only he has 10 accessible aliens and has the Master Control locked.) The aliens he gave Ken were Spitter, Buzzshock, Shellhead, Ditto, Wildvine, Stinkfly, Toepick, XLR8, Sandbox and Snakepit. However, Toepick was later exchanged for Grey Matter because Kenny said that Toepick grosses him out.
In Ben Again, an older Ben 10,000 came to Ben's time zone looking for Professor Paradox, asking the present Ben for directions. On a dangerous situation, the Chronosapiens had gone rogue and Maltruence's temporal beasts were on a interdimensional rampage, causing the time war to start getting out of hand.
When he first appeared, Ben 10,000 wore a white-striped black shirt with short sleevesblack-striped, white shirt with short sleeves, black fingerless gloves, green pants and black boots. in Ken 10, His hair went gray at the back and sides of his head, he went back wearing his original shirt black-striped, white shirt with short sleeves, green pants and black and white boots. In addition to wearing his classic look, he has a belt with pouches for various missions.
In Ben Again, His clothes hadn't changed except his belt buckle has the number 10K on it, and the omnitrix on his left wrist is green.
Ben 10: Omniverse
- Ben Again (first re-appearance)
- Four Arms
- Way Big
- Ben 10,000 appears to favour XLR8 over any other aliens.
- Ben 10,000 told the younger Ben that he would learn that being hero isn't all fun and games. This suggest that Ben 10,000 had experienced some event that caused him to take his hero duties more seriously. The enhanced version of the episode Ben 10,000 reveals that the events that happened when Ben 10,000 was 15 is what caused him to lose his joy of being a hero.
- Ben 10,000 unlocked the Master Control. It is unknown if he is aware of how many aliens are in the Omnitrix or if he has only used 10,000 of the possible 1,000,910.
- Although in Ben 10: Ultimate Alien this Ben 10,000 was not possible in the future, an extremely similar alteration in Ben 10: Omniverse has been created because of Ben having the Omnitrix again.