The Undertaker is arguably the greatest performer in WWE history. He's mastered the art of movement and facial expressions perhaps better than any other wrestler ever has. Usually slow and stone-faced, when The Deadman performs a fast maneuver or makes a genuine facial expression, it inspires a mighty pop from the audience.

One reason why he's become an icon in the social media landscape is his ability to inspire memes and gifs  through his expressions. In recent years, he's become both a symbol of a big sports comeback (Undertaker rising from a casket) and a representative of impending doom (Undertaker breaking out of a coffin to confront Randy Orton). But, perhaps his greatest meme moment came in his intense match with Brock Lesnar at SummerSlam in 2015.

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In a rematch few thought would ever happen, The Undertaker sought to avenge the breaking of his historic WrestleMania winning streak at the hands of The Beast Incarnate. Some thought The Deadman was going to retire once The Streak was broken, but he returned a year later to defeat Bray Wyatt at WrestleMania 31 -- and then set his sights on Lesnar.

Their match in the main event of SummerSlam was much improved from their famous match at WrestleMania XXX, where the Undertaker suffered a concussion early on that forced him to phone it in for the rest of the contest. In the rematch, Undertaker kept his bearings and had a fine match, but it was marred by a bizarre ending. The bell ringer saw Undertaker tap out to the kimura lock and rang the bell, but the referee did not. He finally got his win over Brock by low-blowing him amidst the confusion and forcing him to pass out in the Hell's Gate.

Despite the controversy, the wild ending is not the legacy that most fans think of most from Lesnar and Undertaker's classic battle at SummerSlam. Instead, it's best remembered for one of the funniest and most random moments in the history of wrestling. Near the climax of the match, both men were lying down and Lesnar suddenly sat up in the style of The Deadman, which he'd done the previous SummerSlam against John Cena. The always powerful Beast sat there and laughed at 'Taker in an attempt to show that he was still unfazed by the Deadman's offense.

Undertaker then sat up himself and responded to the laughing Lesnar by mockingly laughing back at him. The usually stoic and stone-faced 'Taker made a face that looked like something out of a cartoon, and all the WWE commentators could say in response was "Incredible moment!" No other words could describe what they just saw.

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That image of Undertaker's cartoonish laugh has lived on as one of the best memes to ever come out of wrestling. Recently Big Cat and PFT Commenter, the hosts of Barstool Sports' wildly successful podcast Pardon My Take, asked the Undertaker how that moment came about when he appeared on their podcast  to promote The Last Ride documentary series.

When asked how that famous moment came about, 'Taker eloquently answered "we did something where we both took bumps and then I did my signature setup...he was up and then I did my set up and he started laughing, so mine was kind of a evil sarcastic laugh back at him and I was shocked the way people, you know, they were so enthralled by the fact that we were laughing at each other."

The world finally got a detailed explanation at one of the most absurd but celebrated images in WWE history. Hopefully that meme will live on in the internet forever, so the delightfully bizarre image of the Undertaker's mock laugh will never have to "Rest In Peace."

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