14-0 Mark Henry (WrestleMania 22)
The Undertaker made it 14 wins on the trot when he put the World's strongest Man, Mark Henry, inside a casket in less than 10 minutes and got the victory in the casket match at WrestleMania 22.
Henry went on to win a few championships after his feud with the Phenom and is still a part of the WWE Raw roster.
Although he is not making regular appearances on television, it has been rumoured that Henry is helping out the upcoming talents backstage. He is likely to be a part of the Andre The Giant Memorial Battle Royal at WrestleMania 33.
15-0 Batista (WrestleMania 23)
The Undertaker won the Royal Rumble in 2007 and set up a WrestleMania match against Batista for the WWE World Heavyweight Championship at WrestleMania 23. The streak continued as the Deadman beat the Animal in an intense bout.
Batista left WWE in 2010 after losing to John Cena in an "I quit" match and returned to the company just before the 2014 Royal Rumble. He then went on to win the Rumble to set up a championship match against his Evolution buddy Randy Orton.
But, somehow, Daniel Bryan made his way into the match and made it a triple-threat before leaving the Superdome with the WWE World Heavyweight Championship. Later, he was a part of the Evolution in their feud against the Shield.
Batista left the company again to pursue his career in Hollywood and is currently working with several movie projects including Avengers: Infinity War. He also has a 1-0 record in MMA as he won his MMA debut by beating Vince Lucero via TKO.