Gimmick Match's Undertaker has Won/Lost
 

Such as Hell In a Cell, Buried Alive, etc. ?

3

At least 3.

4 tops.

Come on now, 4 is a bit excessive DTTS. :-)

8.

Undertaker LOSES GIMMICK MATCHES?!

I don't believe he's ever won a buried alive match

Beat Mankind in the first one. Was attacked by executioner and placed in the grave after he had already won. These days, though...if he has a buried alive match, you can rest assured he's injured and will be out for a few months.

He's lost:
Hell in A Cell, Casket Match, Buried Alive, Body Bag Match. that's all I can remember off the top of my head.

I always thought he had a pretty low win rate in any of 'his' speciality matches, at least televised ones.

Boiler Room Brawl as well.

In his mid and late-career, yes. You're right whitey.
But in his earlier career, he was pretty much dominant in any match-type, especially casket matches.

He lost the second Casket Match.

Undertaker is 12-5 in casket matches. He defeated Kamala, Yoko, Kama twice, Mabel, Kane, The Rock, Heidenreich, Mark Henry twice, Chavo Jr, and Big Show.

He lost to Yoko, Goldust, Vader, Michaels, and Randy/Bob Orton

Also he is 5-4-1 in Hell in a Cell matches...

found this :

Surprisingly, Undertaker is actually 5-5-1 in a match that he is usually associated with as being a master of. He has wins over Mankind, Big Boss Man, Randy Orton, Edge and CM Punk, but has losses to Shawn Michawls, Brock Lesnar, Batista, Kane and Kurt Angle (the Angle match being a multi-man match with HHH, Steve Austin, Rikishi and The Rock as well). There is also the "forgotten" Cell match from Raw where Undertaker & Steve Austin vs. Mankind & Kane ended in a no-contest.

You are correct sir, forgot about the 2010 HiaC 5-5-1

He lost a First Blood MAtch to Austin at Fully Loaded 98.

"Uhh ahh ahh ahh buried alive, buried alive!" - one of Foley's promos before said match.