Wes Green is an old friend of Max Tennyson and also a retired Magister Plumber, who lives in New Mexico. He has a granddaughter, Kai, and knows much about Navajo werewolves.
In the original Ben 10 series, Wes Green is a Native American from the Navajo people, and appears to be in his late fifties to early sixties. He is relatively fit for his age and has long gray hair.
In Omniverse, he is given white, shorter hair and his skin tone is lighter.
As a former Plumber, Wes possesses considerable hand-to-hand combat skills and is familiar with various Plumber equipment. He is also a skilled tracker and expert on Navajo legends.
In Omniverse, he wields the Proto-Tool very efficiently after only observing Rook use it for a short time.
In the enhanced version of Benwolf, it was revealed that Wes and Max sent a Yeti back to its dimension back in their active years before retirement.
Wes only appeared in Benwolf, where he was present when the Yenaldooshi attacked his village. During the hunt for it, he learns about the Omnitrix, and expressed his belief that Ben was turning into a Yenaldooshi since he was bitten by one. In time, they learned that the Yenaldooshi was an alien who had scratched the Omnitrix, allowing it to collect its DNA and give Ben a new alien, Blitzwolfer, but was only transforming him slowly due to a glitch in the Omnitrix.
Ben 10: Omniverse
Sometime between the six-year gap, Wes left retirement and ascended to the rank of Magister. Wes and his granddaughter Kai were exploring the underground sewers of London, when they come across the secret laboratory of Dr. Jekyll and run into the Forever Knights. This sends them all on a hunt for the legendary sword Excalibur. During the battle, Wes fights off several Forever Knights, using Rook's Proto-Tool.