Devlin Levin was first introduced in "Ken 10" He is Kevin 11's son in the future.Devlin was born after one of Kevin's many escapes in which Kevin fled to a colony on Saturn, where he started a family before being captured again. He soon becomes friends with Ben 10,000's son, Kenny, while trying to release his father from the Null Void. Even though he wanted to see his father, Kevin is not interested in seeing him like he does. Feeling heartbroken about this, Devlin eventually understands why Kevin spent most of Devlin's childhood in the Nullvoid and helps the Tennysons battle Kevin. He was attacked by his own father for trying to assist his friend Ken and later was accepted into the Tennyson Family. Like his father when he was Devlin's age, he is able to transform into an amalgam of Ben's original ten Omnitrix aliens. Unlike Kevin during that time period, Devlin can change from an amalgam of aliens back to his human self anytime he wants. Devlin Levin becomes Ken Tennyson's adopted brother.