Peter is a knight of Sumeria. He is part of the group that joins Ash on his quest againts Ruby in Ash vs Evil Dead Season Three.
Peter made his debut in Ash vs Evil Dead episode Tales From The Rift. Alongside his fellow knights Zoe, Marcus and an unnamed 4th guy he joined forces with Ash and Pablo. He and his group were searching for Dalton and eventually Ash, whom they believe is the savior of mankind. After a brief chat with Ash at his home the four knights sworn themselves to protect him.
Eventually, he died by the hands of Marcus when he returned from his recon mission through a dimension rift. The possessed Marcus easily dispatched his partner and then molded Peter's body into his own.
The Marcus-Peter deadite was then defeated by Ash with a little help from Pablo and Zoe.