Simplify the following text for a Grade 9 native English-speaking person.
Original: Undertaker went on to hit Henry with a Tombstone Piledriver and then pushed him into the casket to win the match and keeping his undefeated WrestleMania streak alive improving his WrestleMania record to 14-0 .
Simplified: Undertaker then performed a Tombstone Piledriver on Henry and pushed him into the casket to win the match and improve his WrestleMania record to 14 â `` 0 .