Ben Tennyson/Original

Benjamin Kirby "Ben" Tennyson was a normal ten-year-old kid until he found the Omnitrix, a powerful watch-like device that allowed him to turn into ten different aliens. Though initially immature and clumsy, Ben grew to be a true hero. By the time he was sixteen, he had become famous in not only his hometown of Bellwood, but on Earth and beyond. Ben has also been deputized by the Plumbers and gained more aliens as time progressed.

Appearance
Ben's physical appearance has changed throughout the series from a ten-year-old to a sixteen-year-old. However, he retains some recurring characteristics. He has shaggy brown hair, green eyes, pale skin, and he's quite skinny for his age, though he shows a lot of muscle definition due to being athletic.

When he was 5, as revealed in a flashback of how he first met his future frenemy Mr. Baumann, Ben wore green overalls with a white shirt underneath it. White numbers saying "5 1/2" where on a black square in front of his overalls.

In the original series and Omniverse flashbacks, Ben's usual clothes consists of a black-striped, white shirt with short sleeves, military green cargo pants and black and white sneakers with black stripes. Ben wears the prototype Omnitrix on his left wrist.

In Alien Force and Ultimate Alien, Ben wears a black shirt, blue pants and a green jacket with white stripes and the number 10 on it, and black shoes. Ben wears the prototype Omnitrix in Alien Force and the Ultimatrix in Ultimate Alien on his left wrist.

In Omniverse, Ben wears a black shirt that has a green stripe in the middle with a white 10 and green stripes on the sides of his shirt. He wears brown cargo pants with pockets at the knees and green and white shoes. He later gains a white hooded jacket with green stripes on both arms and a green number 10 on the right side. He wears the Omnitrix on his left wrist.

Personality
Initially cocky, childish and arrogant, Ben's immaturity and attention-seeking behavior often led him to joke around, regardless of the situation. His allies often criticized his attitude, unaware of the fact that he used humor to mask his fears. Despite some childish attitude, he was heroic, caring and generally good-natured, always willing to save others at any time.

Over the years, Ben has displayed good leadership skills, as well as the ability to adapt his attitude to a situation, becoming serious when it's called for. He became more mature, responsible and sensible. He's kind-hearted, willing to sacrifice even his own life for others. His idealistic views and unwillingness to compromise his values – aspects condemned by Azmuth, yet commended by others – sometimes drive him to act against reason, such as helping his enemies if they need it (most remarkably Vilgax). Professor Paradox has praised Ben's good nature, going so far as to say he had the gift to make the right choices at the right moments.

However, when Ben fails to save someone, or if someone gets hurt because of his failures, he becomes angry and much more violent. Perhaps the most notable of these instances is when Kevin willingly mutated himself to succeed where Ben had failed and stop Aggregor, Ben was set on killing Kevin, even fighting Gwen when she refused to help him. He also threatened to hunt down and destroy the Forever Knights once making Driscoll promise to cease the hunting of aliens.

Though often stated to be silly or unintelligent because of his immaturity, Ben is cunning and resourceful when needed, quickly adapting when the Omnitrix doesn't provide him with the alien he wanted.

Later on, Ben starts thinking of himself as more of a superhero than a Plumber, often remarking that he's not a cop, but a superhero. Although he once again became cocky, he retained his selfless and heroic nature.

Powers and Abilities
Ben has been trained in hand-to-hand combat by black belt Gwen, Max, as well as various years fighting aliens, and received a basic Plumber training. He proved to be quite skilled in basic hand-to-hand combat as well armed and unarmed combat, being able to easily dodge shots from Manny's blasters and proceed to disarm him while in human form. Ben was able to hold his own against Pierce, and Max hinted that Ben was a highly skilled fighter, even as a human. Another hint of his exceptional hand-to-hand skill is when he succeeded in the Plumbers' Academy with a 95 out of a 100. He is also a crafty fighter and actually uses freestyle fighting.

It's evident that Ben is smart in some respects, possessing an above average intelligence. It was even stated by Gwen that he really isn't working up to his potential at school. He also has fairly moderate grades. Physics and Chemistry are his toughest subjects, yet he still maintains a B+ average.

Ben has a good memory, as he was perfectly capable of remembering and writing down the mystic rune-like symbols for entering the inter-dimensional realm of Ledgerdomain with just one glance from a distance.

Ben is also a cross dominant, skillfully wielding tools and weapons in either hand, in human or alien form.

Equipment
Ben is the wielder of the Omnitrix (formerly the Ultimatrix and first Omnitrix), which gave him the power to modify his own genetic code in order to turn into various alien creatures. Traditionally, he could only transform into ten aliens at the beginning of both the original series and Alien Force, but he later gains additional forms by either unlocking them or by scanning the DNA of aliens he meets.

When transforming into an alien, Ben gets all the creature's features, including its appearance, voice, all of its unique and special abilities and powers, strengths and weaknesses. Though he mostly retains his personality, there are some cases where the transformation causes change in it, like with Rath and Jury Rigg.

Though he usually uses his alien forms to fight, he can impersonate aliens as he did with Water Hazard to convince P'andor to go home, and though he was unsuccessful at convincing him, P'andor believed him to be Bivalvan.

In addition to transforming into aliens, the Ultimatrix included what is referred as an "evolutionary function", that allowed Ben to evolve his alien forms in order to get upgraded versions of them, referred to as Ultimate Forms.

In addition to the primary transformations and evolutionary function, the Omnitrixes and Ultimatrix can both be used for various purposes. Both have a built in Universal Translator that allows Ben to communicate with most aliens that don't speak English.

The prototype Omnitrix displayed the ability to manipulate and repair genetic damage, a function he used to cure DNAliens and save the Highbreed from extinction. Azmuth also mentioned that Ben could use the prototype Omnitrix to bring back to life any species stored on Primus.

The Omnitrix also has a failsafe to help prevent Ben from dying. If Ben is in mortal danger and the Omnitrix is in recharge mode, it will automatically go into active mode.

Weaknesses
Whenever the Omnitrix times out, Ben is left powerless until he either dodges or switches to a new alien form. In addition to gaining the selected alien's powers, he gains its weaknesses. Additionally, at times the natural biological behavior of certain aliens can override Ben's behavior, such as Big Chill's reproductive phase or Swampfire's blossoming process. Furthermore, any illness Ben is experiencing in his human form will also be affect his alien forms.

Whenever Ben unlocks a new alien form, he is at a disadvantage of not knowing its abilities and weaknesses until he gains experience with using the new alien.

Despite his experience in using the Omnitrixes and Ultimatrix, Ben still does not know every function of them. Due to his inquisitive nature and impatience, he has accidentally unlocked new functions such as the Master Control and the randomizer, which can at times do more harm than good.

Though the current Omnitrix is designed to work only for him, Ben still has not mastered it. According to Azmuth, Ben may get the Master Control on his 18th birthday.

The Omnitrix does not actually mistransform, but rather it is due to Ben hitting the Omnitrix too hard, thereby causing the time-out function to select another alien at random.

Ben has an allergy to peanuts and has a fear of peacocks. He also has coulrophobia, the fear of clowns.

Ben's left eye twitches whenever he tells a lie, but only Kevin appears to notice this.

Ben appears to have a short attention span at times, and more often than not it can get him into trouble.

Though he has matured substantially since receiving the original Omnitrix, he is still a teenager with much to learn and is prone to irrational impulses and recklessness.

Appearances
Ben has been in every episode, movie and short except of the what if episodes, Gwen 10, Goodbye and Good Riddance and Ben 10: Race Against Time, which feature Ben from alternate timelines. Here's a list of all his appearances throughout the series.


 * Ben 10/Episodes
 * Ben 10: Alien Force/Episodes
 * Ben 10: Ultimate Alien/Episodes
 * Ben 10: Omniverse/Episodes



Etymology
Benjamin is a name from the Hebrew name בִּנְיָמִין (Binyamin) which means "son of the south" or "son of the right hand" going back into the Tanakh (called the Hebrew Bible by Christian scholars), a name of one of the sons of Jacob. His name, "Ben," is to create a rhyming effect between his first name and the number Ten. Also, his surname is a reference to 'Ten' of Ben 10.

His middle name, Kirby, was named as reference to comic book artist Jack Kirby.

Trivia

 * According to Azmuth and Professor Paradox, Ben will have a glorious future.
 * According to Azmuth and Sir George, Ben is the same as they were when they were young.
 * According to Natalie Tennyson, Ben does not have good table manners.
 * When Ben was 10, he used to sleep with his teddy bear, called "Furry Freddy." However, Ben defended himself saying that Furry Freddy had his own bed, which happened to be right next to his.
 * Ben's history now has to be read at the Plumbers' Academy. It comprises approximately a "chapter and a half."
 * Gwen's birthday is in December, which would put Ben's in December too, as they both share the same birthday.
 * According to himself,
 * He used to shout the names of his aliens to strike fear into his opponents.
 * His worst subject is Physics.
 * He passed the 3rd grade by choosing C for all the answers on multiple choice tests.
 * His favorite color is green.
 * His favorite food is Chili Fries.
 * His favorite hobby is collecting Sumo Slammers.
 * His worst fear is peacocks.
 * His first crush was Patty Berkinfield from 3rd grade.
 * He has a scar on his body in the shape of New Jersey.
 * Ben has a habit of referring to other members of his aliens' species by the names he gives his aliens.
 * Ben has obtained an honorary college degree from Friedkin University.
 * Ben can play guitar and also snow-board.