Certain numbers will always stand out among historians seeking to encapsulate The Undertaker’s WWE legacy.

That’s due, in no small part, to the number 21, which represents the amount of consecutive victories collected by The Deadman at WrestleMania. That one digit, which just kept growing and growing until Brock Lesnar put a stop to it at WrestleMania 30, became a defining characteristic of The Phenom, a tidy rule of thumb that helped summarize the greatness and longevity of his storied career.

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Paul Heyman may relish being “the one behind the one who put the one in 21 and one,” but focusing on the rise and fall of The Streak does a disservice to other statistics that more succinctly describe The Undertaker’s career. Now, go inside the numbers with WWE.com to learn five important figures that describe The Deadman’s accomplishments to date, and a few challenges that still stand in his way.

15: Number of championships held in WWE

For some, the measure of success in WWE equals a tally of all the titles a Superstar has attained during his tenure. The Undertaker offers ample evidence to back him up in this department.

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Two themes immediately emerge when statistically breaking down The Phenom’s reigns, the more important of which involves his singular dominance in the squared circle. Seven of those championship triumphs come in the form of World Titles, offering examples of his supremacy against the likes of Batista, Sycho Sid and WWE Hall of Famer Edge, among others. Question his toughness and supporters will quickly point out his Hardcore Title victory at Vengeance 2001, too.

Yet the more interesting result of his title tenures may come from the unlikely confirmation that The Undertaker can, in fact, play nice with others. His achievements as part of The Brothers of Destruction are well documented, and are further supported by their two WWE Tag Team Championship reigns and single run with the WCW Tag Team Titles. However, that leaves four other tandems at the top of WWE’s tag team division, periods of time that The Undertaker shared with friends and rivals like “Stone Cold” Steve Austin, The Rock and Big Show.

159: Number of WWE pay-per-view matches

The mere presence of The Undertaker can turn any evening into a main event attraction — and that’s been the case since he made his memorable debut at Survivor Series 1990.

WWE Network: See The Undertaker's WWE debut at Survivor Series 1990

Few could have known that the Superstar introduced in Hartford, Conn., by The Million Dollar Man would go on to become one of WWE’s most important competitors over the next quarter century. Who would guess that 23 show-stealing WrestleMania matches would follow, or 16 goosebump-inducing encounters at SummerSlam, or a breathtaking Royal Rumble Match victory in 10 memorable appearances?

And it’s not just the sheer volume of bouts that makes The Deadman’s run so special. His 91 wins at WWE special events came against all comers, from Jake “The Snake” Roberts at WrestleMania VIII to Goldust at In Your House: Beware of Dog 2 to John Cena at Vengeance 2003. The Phenom took on all challengers, and his outstanding PPV winning percentage to date proves that, more often than not, he came out on top.

2014: The only year missing an Undertaker victory

The 2015 edition of Survivor Series will claim an important place in WWE history, and not just because of the epic match card that will presumably take place.

WWE Network: Watch The Undertaker's only 2014 match at WrestleMania 30

This edition of WWE’s fall classic will also mark the 25th anniversary of The Undertaker’s debut in WWE, as well as the first time the WWE Universe witnessed him earn his way into the winner’s circle. He didn’t just become The Phenom overnight. It took a long time and a lot of defeated opponents to remove all doubt about this supernatural Superstar’s capabilities in the ring.

And what’s more impressive is that he accrued at least one win in every year since his WWE debut, with one notable exception. The Undertaker’s shocking loss to Brock Lesnar at WrestleMania 30 ultimately resulted in a big goose egg in The Deadman’s 2014 win column, which isn’t the only way he associates a zero with The Beast Incarnate.

0: His number of victories against Brock Lesnar

At his highly-anticipated SummerSlam rematch, The Undertaker will resolve or make his peace with a harsh reality in his personal history — namely, his lack of a televised victory in singles competition against Brock Lesnar. Paul Heyman’s prized client collected his third overall victory against The Phenom at WrestleMania 30, a run of success that also includes wins at the 2002 and 2003 editions of No Mercy in addition to their controversial encounter at Unforgiven 2002.

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Should Lesnar continue his dominance, the master of the Tombstone Piledriver will begrudgingly pair that name to another grappling luminary who never succumbed to the power of the urn so often carried by Paul Bearer. The Ultimate Warrior also never lost any of his one-on-one encounters with The Undertaker, all of which occurred before the first anniversary of the The Deadman’s WWE debut.

12: Number of Hell in a Cell Match Appearances

While The Undertaker’s struggles with Brock Lesnar include  a distressing defeat in a Hell in a Cell Match at No Mercy 2002, that result represents the exception and not the rule for The Phenom’s track record inside the insidious steel structure. In fact, The Undertaker owns the record for most Hell in a Cell Match appearances with 12, and is also the co-owner of the record for most wins with six, a tally he shares with Triple H.

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With apologies to the Casket Match, no other specific stipulation sums up The Deadman’s unparalleled dominance so well. The Hell in a Cell Match is merciless, leaving competitors nowhere to run or hide and only way out: Victory by any means necessary. The Undertaker set the bar high for Hell in a Cell Match expectations with his devilish duels against the likes of Mankind and The Game, among others, leaving in his wake a devious dozen examples of the mark still being made by the most influential Superstar of his generation.