Eli J. Brown the Brown Hedgehogis the newest member of T.U.F.F. who asked the The Chief to work with Dudley Puppy and Kitty Katswell. As the newest member of the team, Eli knows a lot of neat tricks in catching the bad guys such as suggesting some new inventions to Keswick such as glasses that allow himself, Dudley and Kitty to see through The Chameleon's disgueses, a Peanutbutter and Jelly sandwich given to Verminious Snaptrap and then tell him that the peanutbutter was actually melted cheese, and a remote-controlled flying device for Bird Brain that flew him to prison. With Eli around, the bad guys stand no chance and sometimes don't even have a chance to attempt their evil scheme.
He would be voiced by his real-world creator of the same name.
Eli uses a portal to go back and forth between his homeworld, Mobius and Petropolis. Although his portal unlike the one Birdbrain tried to use doesn't destroy the user's original universe.
In "Bark to the Future" the Chief told Keswick to make a device that allows Dudley and Kitty to see the Chameleon no matter what he turns into. Which however was his idea. It's unknown if the official creators of the show got the idea from his fanfic or if they just coinidentally got the same idea on their own. The 2nd possibility is the most likely.
Though Dudley and Kitty did't know this until "A DOOMed Valentines Day", Eli secretly hated Eric (Kitty's love interest apart from Dudley) and Becky (Dudley's love interest apart from Kitty)]]. Though at one point in time, Eli actually thanked Eric for bring in the water cause he was thirsty. But didn't say he hated him to keep himself from sounding rude. Also, despite Daisy also trying to break the Kudley romance, Eli can't give any hatred towards her. While he doesn't like Eric, he does hold a liking to his brother, Derek.
Eli is the only agents who apparently can recognize the Chameleon's voice in his disguises and is puzzled that nobody else can.
In some of the T.U.F.F. Agents fanfics, Eli appears to be partners with Kitty's sister, Cat Katswell just as Kitty and Dudley are partners.
As shown in "Kitty Forgets Her Name", Eli appears to prefer to take orders from Kitty and not Dudley as Kitty would listen to his ideas while Dudley wanted to do everything himself.
Recent images showing him with CaseyDecker's OC, Hayai Bunny dressed as a Qittaswell Sister with her giving him a kiss suggests a possible future relationship with one another. Eli-J-Brony even told CaseyDecker that he was allowed to use the character of Eli if CD was ever interested in giving Hayai a love interest.
When Eli and the other TUFF Agents were visitng the Foresgers during the fourth of July, his idea of TUFFRangers was brought to life for one day by Canis Lupis and he fought alongside Edward, the White Foresger against Verminious Snaptrap, Birdbrain, The Chameleon, Rocket Sam, and Poluton's Poluters.