Ben Tennyson (Classic)

Benjamin "Ben" Kirby Tennyson (voiced by Tara Strong) is a typical ten year-old boy — he plays video games, rides his bike, and often gets into mischief. Graham Phillips portrays Ben Tennyson in the live action film Ben 10: Race Against Time.

During a walk an alien pod crashes to earth Ben investigates and finds the Omnitrix, which latches to his arm. Unable to remove it, he uses its powers to become a super hero. However, he finds the job trickier than he imagined, especially with the evil alien warlord Vilgax pursuing him relentlessly to retrieve the Omnitrix. No matter what bizarre form Ben takes, inside he is still the same mischievous 10-year-old boy. He is something of a glory hog, sometimes taking credit that he does not deserve.[1] He also tends to be a sore loser, especially when it is Gwen, with whom he shares a love-hate relationship who outdoes him. Ben is not above using the Omnitrix to pull pranks, even during urgent situations.[2] In spite of all this, Ben is good-hearted and will stop at nothing to protect his family or anyone in danger. Even when not in alien form, Ben's resourcefulness has saved himself and others from many a dire situation, especially when the Omnitrix cannot activate or does not provide him with the form he originally wants. His most frequent catchphrase, usually said when something goes wrong, is "Aw, man!" His others include "It's hero time!" and "Going hero!"

Twenty years into the future, Ben (this version voiced by Fred Tatasciore) has become a full-time superhero. He no longer bothers to conceal his identity, as he is recognized everywhere as Ben 10,000 or Ben 10-K. He also has 10,000 alien forms, hence the name, and has once again unlocked the Omnitrix's master control function, allowing him to switch forms at will. Having been fighting crime for such a long time, Ben 10,000 has grown into a more strict and serious character, though his interaction with his past self in the episode "Ben 10,000" causes him to lighten up somewhat. 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 grey outlines in place of the ordinary blue, as well as being considerably faster. Ben eventually has a son named Ken, whom he gives an Omnitrix of his own in the episode "Ken 10".

In the sequel, Ben 10: Alien Force, Ben (voiced by Yuri Lowenthal) is a much more mature and resourceful character, having learned the value of teamwork through his role as a goalkeeper for his soccer team; at the same time growing out of his childish antics. His relationship with Gwen is also improved; they no longer fight, and their quips about one another are more friendly. He now sports a black shirt, a green jacket with a white vertical line and the number 10, while his soccer uniform resembles his original clothing. He found a way to remove the Omnitrix roughly five years before the series began, allowing him to live a normal life. When Grandpa Max goes missing, he teams up with Gwen and a reformed Kevin to find him. The Omnitrix has been recalibrated, giving access to a new set of alien forms; in addition, it reconfigures into a more watch-like shape. It also carries a new weakness: if Ben's aliens are hurt when the Omnitrix times out, so too is Ben hurt as a result. Contrary to the Omnitrix's previous ill-timed deactivations, the new recalibrated Omnitrix appears to deactivate more or less to Ben's will, and can be used multiple times in succession, though its power will eventually deplete and will require time to recharge. Although he, like Gwen, is a descendent from the Anodite race, Ben does not bear their powers.