30-year-old Allin says he's on a mission to surpass what other wrestlers have done before him, not just inside the ring, but outside, too, "pushing the boundaries."

"That's been my whole MO since AEW started," Darby told Mojo Muhtadi, adding, "That's why it's so important for me to meet up with guys like [Travis] Pastrana, and make stuff happen. Do stuff that no wrestler's ever done before."

That's when Darby revealed his intention ... to climb one of the most unforgiving mountains on planet Earth.

"The thing I'm going to be doing next year that no wrestler's done before is climb Mount Everest. You heard it here first."

Of course, at 29,035 feet above sea level, Everest, located in Nepal and Tibet, is one of the most unforgiving and challenging mountains to climb. In fact, hundreds of climbers have died attempting to summit the peak.

Around 4,000 have successfully climbed the mountain.

As daunting a task as it is, Allin's known for his death-defying stunts in and outside the squared circle ... and he seems up for the challenge, telling us he's looking for his "next rush."

You may recall ... last August, DA completed a 96-foot jump over his home in a jeep, calling it the "sketchiest stunt" he had ever attempted.

When we spoke to Darby about the insane jump, he told us he was "terrified" because the stunt car had no breaks or speedometer.

Travis Pastrana helped organize the stunt for Darby last year, and even the notorious action sports star told Darby there was a good chance he'd break his back.

The X Games gold medalist introduced us to Brandon Taylor, who nailed a motocross backflip at his famous "Pastranaland" compound in Maryland ... and the clip is pretty sick!