Generator Lan 10 is a series that also adds Ben 10: Ultimate Alien so it's a whole crossover series. The main character is a boy named Lan.
The story follows Lan Skyedex, a normal 12-year-old preteen. When summer vacation arrives, Lan goes with his sister, friend, and grandpa on a camping trip. While they were hiking, Lan found the Mastertrix, a device that can not only turn him into aliens and fusion aliens like Ben 10, but can also turn himself into machines and weapons like Generator Rex. So with his friends, Lan tries to fight the evil Stavblast with the Mastertrix. But he must first unlock new aliens and machines from the Mastertrix as well as it's true and full power.
Lan Skyedex (main character and holder/main user of the Mastertrix)
Sarah Skyedex (2nd main character and younger twin sister of Lan, will have telekinesis powers later on)
Arrow (3rd main character and friend of Lan, is an orphan, and will also have Osmanian powers later on)
Nathan Skyedex (4th main character, Lan and Sarah's grandpa, worked for Providence and Plumbers)
Stavblast (main villan)
Stavblast Jr. (2nd main villan and Stavblast's son)
Androids (minor villans, created by Stavblast, but Android 62926 (a.k.a. Kress) will be turned into a hero)