Timeking

The Timeking is Paradox's arch enemy. In 10 again he turns Ben 10 again.But he is later defeated by Ben when he is 26! Timeking appears again in Ben 10 universe vs. DC universe where he supported Ben's side to defeat the Darkseid and separated the universes.

He can go back in time,just like Paradox. He can turn anyone, or anyone into any age he wants.

Ken 10
Still the same age, Timeking appears still. In Journey To The End Of The World It is reavled that he kills Ben,Ken and the others and rules the world. But thanks to Ken, He stopped it. He also teams up with The Veggie King in the Season Finally. If Ken didn't stop him, he would've killed Ken.

Realitives
Timeking has a son, called the Time Prince. His son has a copy of the Omegatrix. His daughter-in-law's name is Starr. Timeprince and Starr had a kid, who's name is Time JR.