#1. AJ Styles' boneyard match and the consequences
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With no Undertaker physically present, AJ Styles appeared on the ramp with Luke Gallows & Karl Anderson and wasted no time in taking shots at The Undertaker. He continued to 'expose' him outside his Deadman persona, further indicating that The Undertaker is truly done with that direction after 16 years.
With his match against The Undertaker official for WrestleMania 36, he decided to announce that he wants a stipulation added. It's a 'boneyard match'. We have no idea what that is and from the sound of things, most people don't either.
The intention seems to be to end The Undertaker's career, but the way the feud is built (and the fact that it's WrestleMania), it seems all too obvious that The Phenomenal One will lose at WrestleMania for the first time in 4 years.
Either way, the boneyard match will not serve to bring back The Deadman. Instead, it's likely to further cement the new gimmick that he has seemingly established.
Also read: WrestleMania 36 - 5 interpretations of a Boneyard match