The Undertaker's Wrestlemania Streak

Mark William Calaway (born March 24, 1965) is an American professional wrestler better known by his ring name The Undertaker. He is signed to WWE and is the company's most tenured competitor. Mark Calaway began his wrestling career with World Class Championship Wrestling (WCCW) in 1984. He joined World Championship Wrestling (WCW) as "Mean" Mark Callous in 1989. When WCW did not renew Calaway's contract in 1990, he signed with the World Wrestling Federation in October and, after shortening his name from Kane the Undertaker to simply The Undertaker, has remained with the company since.

Because of his gimmicks, Undertaker has a number of specialty matches associated with him: the Casket match, the Buried Alive match, the Hell in a Cell and the Last Ride match. An important part of the character is his half-brother Kane, who was introduced in 1997 and with whom he has both feuded and teamed as the Brothers of Destruction.

The Undertaker holds an unrivaled record of being undefeated at WrestleMania, WWE's premier pay-per-view event, with a 19–0 record. Among other accolades, Calaway is an eight-time World Champion having won the WWF/E Championship four times and the World Heavyweight Championship three times as The Undertaker, and the USWA Unified World Heavyweight Championship once under the Master of Pain character. The Undertaker is also a seven-time World Tag Team champion: a six-time WWF Tag Team Champion and one-time WCW Tag Team Champion. The Undertaker was the winner of the 2007 Royal Rumble and became the first man to enter the annual event last and win. Calaway is the only remaining WWE wrestler to have also appeared on the first episode of its Raw program.

1-0 Wrestlemania 7 1991 Super-Fly Jimmy Snuka

2-0 Wrestlemania 8 1992 Jake The Snake Roberts

3-0 Wrestlemania 9 1993 Giant Gonzalez
Undertaker's only disqualification win at WrestleMania

Wrestlemania 10 1994 - No Match
The rumour is that the Undertaker would have faced Randy Savage 

His rivalry with Yokozuna culminated in a WWF Championship casket match at the 1994 Royal Rumble. During the match, champion Yokozuna sealed The Undertaker in the casket with the assistance of several other villainous wrestlers to win the match. The Undertaker appeared from inside the casket on the video screen, representing his spirit, warning that he would return. However, that was not at Wrestlemania. Presumably the Undertaker must have been injured and needed the time off.

After WrestleMania X, Ted DiBiase introduced an Undertaker back to the WWF. This Undertaker, however, played by Brian Lee, was an impostor Undertaker (dubbed the "Underfaker" by fans) and led to the return of the real Undertaker at SummerSlam, appearing as a new version of his original Deadman persona, replacing grey with purple. The Undertaker defeated the impostor after three Tombstone Piledrivers. Several weeks later, The Undertaker injured his orbital bone near his eye, forcing a period of absence for surgery, until his return at Survivor Series. The Undertaker returned at the 1995 Survivor Series, wearing a Phantom of the Opera-like, grey upper mask. In the main event of the 1996 Royal Rumble, The Undertaker was unmasked in a WWF Championship match against Bret Hart, when Diesel interfered in the match to cost the Undertaker the championship.

4-0 Wrestlemania 11 1995 King Kong Bundy

5-0 Wrestlemania 12 1996 Diesel (Kevin Nash)

6-0 Wrestlemania 13 1997 Sycho Sid (Sid Vicious)

Wrestlemania 13 1997 WWF Championship

7-0 Wrestlemania 14 1998 Kane (1st Time)

8-0 Wrestlemania 15 1999 Big Boss Man (Hell In A Cell)

Wrestlemania 16 2000 - No Match
The rumour is that the Undertaker would have faced the Big Show 

In September 1999, The Undertaker went on a four month hiatus from WWF due to a groin injury. In January 2000, one month before a scheduled return at the Royal Rumble, he tore a pectoral muscle. I would assume that they had planned on having him return at the Royal Rumble and set up a match for Wrestlemania. But because of his injuries he missed the Royal Rumble and Wrestlemania. 

9-0 Wrestlemania 17 2001 Triple H (1st Time)

10-0 Wrestlemania 18 2002 Ric Flair 
In Toronto... I was there!

11-0 Wrestlemania 19 2003 Albert (Big Show's Partner)

12-0 Wrestlemania 20 2004 Kane (2nd Time)

13-0 Wrestlemania 21 2005 Randy Orton

14-0 Wrestlemania 22 2006 Mark Henry (Casket Match)

15-0 Wrestlemania 23 2007 Batista

Wrestlemania 23 2007 World Championship

16-0 Wrestlemania 24 2008 Edge

Wrestlemania 24 2008 World Championship

17-0 Wrestlemania 25 2009 Shawn Micheals (1st Time)

18-0 Wrestlemania 26 2010 Shawn Michaels (2nd Time)
Career vs Streak Match - Ended Shawn Micheals' Career

19-0 Wrestlemania 27 2011 Triple H (2nd Time)

Overall, the Undertaker has faced 16 different wrestlers at Wrestlemania. He has faced Kane, Shawn Micheals, and Triple H twice.He will be facing Triple H for a third time this year, making Triple H his top opponent at Wrestlemania. He has had one Casket Match (against Mark Henry) and one Hell In A Cell Match (against the Big Boss Man). However, this year's match against Triple H will also be a Hell In A Cell Match. He has won by pin-fall, submission, and disqualification. The Undertaker has done it all at Wrestlemania, and if he defeated Triple H this year his record will be 20-0 and he will always go down in history as the greatest Wrestlemania performer. 

 I still think his greatest opponent will always be Kane!