Without question, one of the biggest highlights of WrestleMania 36 was the Undertaker's Boneyard Match, which main evented the first night of the two-night show. The Boneyard Match received universal acclaim from fans and critics alike, and alongside night two's Firefly Fun House Match has helped to usher in the new WWE era of cinematic pre-taped matches. The match, which might have been the Undertaker's last, was beloved by everyone -- well, nearly everyone.

Perhaps the one holdout who didn't enjoy the Boneyard Match was the Undertaker's opponent, A.J. Styles. While the Phenomenal One got in some good shots on the Phenom, the end of the match was all Undertaker. The Deadman managed to fight off Styles' hooded minions, beat down Styles' OC stablemates Gallows and Anderson so badly they'll never appear in WWE again, teleport out of AJ's clutches, choke-slam Styles off a farmhouse roof, and finally, bury AJ alive. The match ended with Taker unveiling AJ's tombstone before driving off on his American Badass chopper, while AJ's hand poked up out of the grave behind him.

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It must have taken Styles quite a while to dig himself out of that grave, since he wasn't seen back on Raw for over a month until making a surprise appearance at the Last Chance Gauntlet Match to take Apollo Crews' spot in the Men's Money in the Bank match (which he won). AJ cut a promo to assure the audience that, despite his apparent death at WrestleMania, he was neither a ghost nor a zombie, and challenged the notion that he had lost the Boneyard Match at all, since no one had ever outlined how exactly one goes about winning (or losing) a Boneyard Match.

While AJ talked a big game on Raw trying to no-sell any lingering after effects of the shellacking that he took in the Boneyard Match, it appears that he may not be able to shake off the beatdown he suffered at the Undertaker's hands quite as easily as he'd like the WWE Universe to believe.

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While battling his way to the top floor of WWE headquarters, Styles began hunting for Rey Mysterio. After briefly mistaking a framed poster of Mysterio for the real deal, Styles began jawing with the poster, trash-talking about what he was going to do to the Master of the 619 when he found him -- until he turned the corner and came face to face with his greatest fear: the Undertaker himself.

Of course, it wasn't the Deadman in the flesh that froze AJ in his tracks, but a giant framed poster. AJ's fear of the Phenom ran so deep that even the poster seemed to terrify him. He tried to shake it off, until the door of a nearby room opened to reveal a coffin and other spooky Undertaker-themed decorations. Styles tentatively approached the coffin to see if the Undertaker himself was in it, and while it was implied that Taker wasn't actually residing inside, AJ still howled in terror as the door swung closed.

While AJ did his best to recover after escaping the Undertaker-themed room, he never really got back into a groove in the remainder of the match after being forced to confront his new Undertaker Phobia. Alongside Daniel Bryan, he meekly slunk away after being scolded by Mr. McMahon for attempting to brawl in the boss's office. While he made a brief comeback, reaching the top of the ladder right ahead of Smackdown's Baron Corbin, Styles ended up coming up just short in his quest for the briefcase, fumbling it into Otis' waiting hands while fighting off Corbin for control of the case.

While real-world PTSD is a serious issue that should never be made light of, in the make-believe world of professional wrestling, AJ Styles' "Undertaker Phobia" is the perfect comedy gimmick for AJ's blowhard heel character. Many fans were disappointed when AJ showed up a month after his burial alive seemingly no-selling any long-term ramifications of the bout. In the past, wrestlers coming back from that kind of kayfabe storyline injury would have incorporated it into their characters, so it's nice to see that WWE isn't totally ignoring any fallout from the Boneyard Match for AJ's character. Giving him a comedy gimmick in which AJ is "haunted" by the Undertaker like Principal Seymour Skinner is haunted by his past in Vietnam is a perfect fit with both Styles' and Undertaker's characters that (so far) doesn't cross the line into mocking genuine PTSD.

It appears that WWE will be moving forward with this storyline, as AJ was seen the day after Money in the Bank watching a commercial for WWE's The Last Ride documentary series. While the vignette finished with AJ hurling popcorn at the screen in some combination of anger and disgust, it's worth noting that he was wearing an Undertaker t-shirt in the scene, so it's possible his phobia may begin evolving into Stockholm Syndrome in the coming weeks.

While it remains to be seen where WWE ends up taking the storyline and how much actual involvement the Undertaker will end up having in it, so far it's been an inspired idea on WWE's part. It's been a great way to give the Phenomenal One a new creative direction after the release of the OC, while also being a unique way of gaining more mileage out of one of the most exciting feuds WWE had this WrestleMania season -- without even needing the Undertaker to make an in-person appearance. If it does end up leading to another Styles vs Undertaker match somewhere down the line, WWE fans will be shaking in excitement -- while Styles is secretly shaking in his boots.

Further Reading: Undertaker vs Kane: WWE's WILDEST Family Rivalry Ever, Explained