|The characters and/or events depicted in this article belong to an alternate timeline or dimension.|
|Home World||Earth (alternate timeline)|
Gas Line Employee
|Relatives|| Max Tennyson (father)|
Sandra Tennyson (wife)
Ben Tennyson (son)
Gwendolyn Tennyson (niece)
|Alternate Counterparts|| Carl Tennyson (Main Timeline)|
Carl Tennyson (RAT Timeline)
|Voice Actor||Dee Bradley Baker|
|First Appearance||Goodbye and Good Riddance|
Carl wears a green shirt with gray pants.
Carl is a very calm person who was trying to impress his father by getting a new job and leaving his old one.
In Goodbye and Good Riddance, Carl was shown to resent Max, as his work as a Plumber prevented him from spending time with his family. He found out about the Omnitrix when Vilgax destroyed their house and held him hostage, leading to Cannonbolt saving him. He later assisted Ben, Gwen, and Max in defeating Vilgax, and inside a gutter, he turned a gas pipeline on and set fire to it while XLR8 saved him and Vilgax was caught in the explosion and was supposedly killed. He offered Max dinner but since Vilgax had destroyed their home, he couldn't make dinner. Max told him that he could cook something in the Rust Bucket. Knowing Max's weird taste for food, he said that it would be better to go to a restaurant.
- Goodbye and Good Riddance (first appearance)