As the old saying goes, you can never say never when it comes to WWE. Well, we're saying never. 

In the past few years, we've seen a lot of records broken in sports-entertainment. The New Day became the longest reigning Tag Team Champions of all time. A Gauntlet Match on Raw became the longest bout in WWE history. Asuka's undefeated streak eclipsed Goldberg's. Heck, two records were broken in one night at the Greatest Royal Rumble event alone when Daniel Bryan broke Rey Mysterio's record for longest time in a Rumble bout, and Braun Strowman topped Roman Reigns for the most eliminations in a Rumble with 13. 

Records, of course, were made to be broken. We've uncovered four records, though, that might as well be made out of vibranium, because no one is smashing them. Not even Braun Strowman.

The Undertaker's 21-win WrestleMania Streak

The Streak may be a thing of the past, but The Undertaker's 21 straight wins with zero losses on The Grandest Stage of Them All is still the stuff of legend. For more than two decades, The Deadman beat every single WrestleMania opponent who was put in front of him in an act of grit, skill and determination we will never see again in sports-entertainment. Currently, no one is even in the running. What’s more, we’ll likely never witness another Superstar compete in 26 bouts at WrestleMania like The Undertaker. 

Mr. McMahon's WWE Title win at age 54

After defeating Triple H to become WWE Champion, Mr. McMahon announces he is relinquishing the title.

Sure, Mr. McMahon may have a heart, 206 bones and whatever else makes up a human body, but it’s clear that the WWE Chairman is made of something different than the rest of us. There’s a reason he’s known as The Genetic Jackhammer, after all. That’s why Mr. McMahon was able to capture the WWE Title at 54-years-old — an age when the biggest challenge most men face is another prostate exam. Who else is going to win the WWE Title in their fifties? Who else is going to even try? Well, maybe John Cena.

Nicholas' Raw Tag Team Title win at age 10

Ten years old. 10! At an age when most kids are struggling to build the coolest town in Minecraft, a boy named Nicholas was winning the Raw Tag Team Titles alongside Braun Strowman at WrestleMania 34. Randomly plucked out of the crowd by Strowman, who showed up to WrestleMania without a partner and desperately needed one, Nicholas became, by far, the youngest champion in WWE history thanks to Strowman's dismantling of Sheamus & Cesaro. He may have given up his title so he could get back to the fourth grade, but Nicholas' record will never be broken. Unless some really strong baby comes along.

Bruno Sammartino's 2,803-day WWE Championship reign

Bruno Sammartino’s stats are untouchable. All told, Sammartino’s two reigns as WWE Champion totaled more than a decade, with his longest reign clocking in at an astounding 2,803 days. The WWE Hall of Famer defended against a never-ending supply of lethal villains that included Killer Kowalski, Gorilla Monsoon and Stan Hansen. Sammartino was revered as a fighter, a sports-entertainment icon and the WWE Champion against whom all others will forever be measured. And his record will never be broken.