After making two dark match appearances under his real name in March 1989, Earthquake joined the WWF full time in September 1989. In his first match after signing on, a dark match on September 21, 1989, he was known as Earthquake Evans and managed by Slick. Earthquake then made his WWF television debut on the November 11, 1989 edition of WWF Superstars of Wrestling, where he was planted in the audience as a normal spectator at the taping held in Wheeling, WV. During an in-ring interview with Gene Okerlund, Dino Bravo challenged The Ultimate Warrior to a strength competition. In order to demonstrate, Bravo and manager Jimmy Hart suggested that they pick a random audience member to come into the ring and sit on the backs of Bravo and the Ultimate Warrior as they did push-ups to see who could do the most. The Ultimate Warrior agreed, and Hart, after pretending to look around the audience, centered his attention on the very large Earthquake who was sitting in the audience in casual clothing and appeared surprised. Earthquake came down into the ring, identified himself as "John from West Virginia" and proceeded to sit on Bravo's back as he did a set of push-ups. During the Ultimate Warrior's set, however, Earthquake jumped down onto the prone Ultimate Warrior using a seated senton that was adapted to be his signature move. Bravo and Tenta then beat and unleashed multiple big splashes on the prone Warrior. Both then celebrated as Earthquake was inaugurated into the WWF as a heel with Hart as his manager. Earthquake was pushed as The Canadian Earthquake — and by WrestleMania VI, simply Earthquake - an unstoppable monster heel who often sent his opponents out on a stretcher after repeatedly hitting them with his sitdown splash.
Earthquake's first PPV appearance was when he replaced Barry Windham on Randy Savage's team at the 1989 Survivor Series. Earthquake survived the match, along with Savage and Dino Bravo. He made his WrestleMania debut at WrestleMania VI, defeating Hercules.
Earthquake's career peaked when he entered a feud with Hulk Hogan. The feud exploded in May 1990, when Earthquake snuck up on Hogan from behind during a segment of The Brother Love Show (on WWF Superstars of Wrestling) and repeatedly crushed Hogan's ribs with his "Earthquake splash." Eventually, Hogan recovered and gained revenge on Earthquake and defeated him in a series of matches across the country, starting with Hogan's countout victory at SummerSlam 1990. Hogan and Earthquake were the final two participants in the 1991 Royal Rumble, with Hogan getting the victory.
After his stint with Hogan, Earthquake attained another WrestleMania victory, defeating former Hart stable mate Greg Valentine at WrestleMania VII.
After WrestleMania VII, Earthquake instigated a feud with Jake "the Snake" Roberts when, in their match that aired on WWF Superstars of Wrestling, he "squashed" Damien with his Earthquake splashes; Earthquake had tied up Roberts in the ropes before going on his rampage. In reality, Roberts' bag — one of two left at ringside for the match — contained pantyhose stuffed with hamburger, and a small motor to simulate a "live snake." When the match aired on WWF Superstars of Wrestling, footage of Earthquake landing on Damien was interrupted with cutaway shots to that show's "Events Center," although the incident aired uninterrupted and uncensored during WWF Prime Time Wrestling the following week. Later, Earthquake participated in a skit on WWF Prime Time Wrestling where he cooked "Quakeburgers" on a grill and served them to co-hosts Vince McMahon, Bobby The Brain Heenan, and Lord Alfred Hayes; later, Earthquake revealed that the meat was ground from Damien's carcass. Heenan had already eaten 3 or 4 of the Burgers and Hayes was curious about the meat. Earthquake mentioned the animal from which the meat was taken rhymed with quake and Hayes said they were snake burgers. Heenan got sick and nearly threw up. Vince was angry over this and knocked the tray out of Earthquake's hands which knocked all the burgers onto the floor. Roberts and Earthquake feuded throughout most of late spring and into the summer.
Later in 1991, Earthquake formed a tag team with Typhoon (who had previously wrestled as Tugboat before turning heel) called The Natural Disasters, managed by Jimmy Hart. Initially a heel tag team, the duo feuded with the Legion of Doom over the WWF World Tag Team Championship, but were unsuccessful. Later, the Disasters turned face when Jimmy Hart betrayed them and joined forces with Money Inc., a team composed of Irwin R. Schyster and Ted DiBiase; Money Inc. had just won the tag titles from the Legion of Doom. Although Earthquake and Typhoon eventually won the tag titles (and defeated the Beverly Brothers at the 1992 SummerSlam pay-per-view to retain the titles), it wasn't long before Money Inc. regained the belts.
Earthquake left the WWF in January 1993 after losing to Bam Bam Bigelow the night after the Royal Rumble, but returned in January 1994 when he assisted Bret Hart in a match with Shawn Michaels by countering Diesel's interference. He defeated Adam Bomb in a quick squash match at WrestleMania X. He then engaged in a short feud with Yokozuna, with whom he had a sumo match on Raw.
Earthquake was scheduled to face Owen Hart in a King of the Ring qualifying match. However, during a May 14, 1994 house show in San Jose, California, Earthquake had been injured by Yokozuna and Crush. Footage of Yokozuna hitting a Banzai Drop at the show was televised before the qualifying match to explain his absence in which Doink the Clown was his replacement. He again disappeared from WWF thereafter.
He resurfaced in the WWF on the May 25, 1998 episode of Raw is War under the name Golga. He wrestled under a mask as one of the Oddities and the character had a fascination with Eric Cartman from the TV series South Park, but disappeared in 1999 when all of the Oddities left.
He did however return to the WWF one last time in 2001 with the Earthquake gimmick, where he was one of the participants of the 20 Man Gimmick Battle Royal match at WrestleMania X-Seven. In December of the same year he also worked a tryout dark match against Joey Abs before an episode of SmackDown.
Earthquake died of bladder cancer on June 7, 2006.