The Undertaker isn't generally much of a talker, and is much more interested in letting his actions speak for him. And we hear even less from him out of character - as he has been quite good at keeping up kayfabe.
But just the other day the Deadman showed up as a surprise at a University of Texas football practice and you can check out video of his speech below. You can also check out a transcript at the USA Today website:
Undertaker live at practice. https://t.co/ynueZWzIK9— Texas Football (@TexasFootball) March 23, 2017