The Undertaker is a taxidermist turned Crimelord from an alternate future of Earth-8162.  At some point in his career he bioengineered the Plaguedog, canine monstrosity he used to kill his enemies.
 
Because Death's Head had begun accepting contracts on his lackies, the Undertaker decided to have Death's Head eliminated.  He sold a building to Death's Head's partner, Spratt, for them to use as an office and then set Plaguedog up there to kill them when they arrived.  However, Spratt, despite being alone as Death's Head was on a mission, managed to kill the dog unbeknownst to the Undertaker.
 
He then hired the mercenary Big Shot to kill Death's Heads and Spratt but Big Shot, after several attempts, was not successful.
 
His current whereabouts are unknown.