Ben Kirby Tennyson was a 10-year-old boy who hated school. He was bullied by a kid named Kash. When a boy was being bullied by Kash, he got the urge to go over and help him. However, he was wedgie on a tree like a flag. Ben was going on a trip with Max Tennyson, but also found out that his cousin Gwen Tennyson was joining on the summer vacation. Ben does not like Gwen because they were both born at the same time, on the same day, in the same year. So this complicates things when their birthday comes around. While Ben was walking around in the forest, he saw the omnitrix. The omnitrix jumped on Ben's left hand, and instantly turned him into a flame alien named Heatblast. Using his powers for good, Ben decided to become a hero and got 10 aliens.
As a much older and experienced omnitrix wielder, Ben decided to put his hero days behind him and act like a normal teenaged kid. However, when his Grandpa needed help Ben eventually put the omnitrix back on and got 10 new aliens. He was joined by his ex-enemy Kevin Levin, and his cousin Gwen. They became the heroes of earth, and protected it from human, alien, and magic threats.
Ben has the most powerful weapon in the universe. This weapon is called the Omnitrix. The Omnitrix holds over 1,900,003(one million nine hundred thousand and three) aliens. However, Ben only is allowed 10 at a time, but, when the Master Control is unlocked by either Ben or Azmath, he can control all aliens. In the original Ben 10 game/TV show he started off with 10 aliens and 10 alien species. He got to control Diamondhead, Fourarms, GhostFreak, Grey Matter, Heatblast, Ripjaws, Stinkfly, Upgrade, Wildmutt, and XLR8. A list of aliens and abilities are below:
- Diamondhead was a Petrosapien: A Petrosapien is extremely dense and their whole entire body is made of a near invulnerable diamond. They live on the world Petropia.
- Fourarms is a Tetramand. A Tetramand is a super strong alien with four muscular arms, enhanced durability and almost never ending endurance. Their Home planet is Khoros.
- Ghost Freak is a Ectonurite. Ectonurites are one eyed ghost aliens with a black eye. They have the power to travel through any obstacle and become invisible. Their home world is Anur Phaetos.
- Stinkfly is a Lepidopterran, an insect-like alien from the planet Lepidopterra. They can shoot goop from their mouth and eyes, and they can fly.
- Ripjaws is a Piscciss Volann from the planet Piscciss. These aliens have jaws that can rip through steel. They can swim fast and breath under water, but when they are up top they can only breath for a short time.
- XLR8 is a Kinecelearn alien from the planet Kinet. Kincelearn's can run super fast and they have enhanced reflexes.
- Wildmutt is a Vulpimancer from the planet Vulpin. Vulpimancers have great agility and they have the sense of smell to replace the sense of sight.
- GreyMatter is a Galvan. One of the Galvan, Azmuth created the Omnitrix which Ben uses. Galvan's are super smart, but they are also prideful. They think of themselves to be the smartest beings in the universe(which is sort of true).
- Heatblast is a Pyronite. Pyronites are like living fire, it is said that their home world is a sun!
- Upgrade is a Galvanic Mechamorph that can control mechanical stuff and upgrade it when attached. Upgrade has a hard time controlling things that are alive, and electrified ones also.
- Cannonbolt is an Armadillo-like alien called a Arburian Pelaroda. They roll into a ball and can rotate at a high rate of speed to travel.
- Wildvine is a plant-like alien called a Florauna.they have the ability to stretch their bodies, regenerate limbs, throw gas pods, and control plants.
- Upchuck are small aliens called Gourmands. They have large stomachs and four tongues which they use to eat any inorganic material, then spit it out with explosive force.
As a 15-year-old high school kid, Ben's old omnitrix becomes new. He also gets a new set of aliens. Ben gets Swampfire, Echo Echo, Humungousaur, Jetray, Big Chill, Spider-monkey, Brainstorm, Goop, Chromastone, and Alien X.
The original game and television show is voiced by Tara Strong. She has voiced numerous characters in video games and in television. In alien force, Yuri Lowenthal voices Ben in the game and television show. He is also voicing Ben Tennyson in Ultimate Alien.