Matt Damon snuck onto Jimmy Kimmel Live! on Friday, escalating his faux-feud with ABC late-night host Jimmy Kimmel as the latter taped the last of five shows in New York City.

The Oscar winner entered the stage of the Brooklyn Academy of Music’s Howard Gilman Opera House incognito, dressed as Frankie Focus, New York State’s new mascot promoting restrictions on smartphones in classrooms. In his monologue, Kimmel described Frankie as a “neon Chewbacca with glasses on” and a “giant florescent monster.”

Then Kimmel invited Frankie on stage, and the mascot immediately started ragging on him, saying he could tell the comedian didn’t get a college degree from watching his “stupid” monologue. “Hiya, everybody! Isn’t he dumb?” Frankie asked the live audience.

Kimmel said he wasn’t going to be insulted by “a hot green sewer Labubu,” and Frankie contended he wasn’t going to be insulted by “a guy who looks like they dragged Jimmy Fallon out of the Gowanus Canal.”

Finally, Kimmel grew suspicious and yanked the head of the mascot costume to reveal Damon underneath. “I made it on the show!” the actor exclaimed, joyously.

When confronted by Kimmel, the Oppenheimer star explained why he was dressed as Frankie, saying it wasn’t “a sex thing.”

“Look, I wore this costume because it’s the last chance to get on the show. I know we’ve had our differences over the years, but I just I wanted to be here tonight for your last show ever,” he said. “I just want to say goodbye.”

Kimmel informed him it wasn’t the last show, and Damon seemed confused. “But the president cancelled you,” he said, referring to Kimmel’s recent, politically-charged suspension. “Which I was a big fan of, by the way. I mean, when he said you had like zero ratings and no talent, I was like, I’ve been saying that for years.”

And when Kimmel told Damon he was only off the air for three nights, Damon said, “Are you serious? Is there, like, some kind of appeals process? F***k! This sucks!”

Kimmel eventually got Damon to leave, pointing out he had “real movie stars to talk to” that night and asking Damon if he’d ever heard of Tom Hanks.

“Have I heard of Tom Hanks? I’m Private Ryan, dips***,” Damon replied. “Tom Hanks saved me.”

To that, Kimmel quipped, “And America will never forgive him for that.”

Damon finally took his leave, but he took Kimmel’s mother, Joan, with him. “I was lying about the costume,” he told Kimmel from the aisle. “It is a sex thing.”

Jimmy Kimmel Live!, Weeknights, 11:35/10:35c, ABC