The zombie pirate head is an NPC found in the quest Pieces of Hate.
He served as one of Rabid Jack's loyal pirates and was subsequently killed during the Battle of the Archipelago, before later being revived through unknown means. Sometime in his service, he was selected for the Barrelchest Mk II project.
As a Barrelchest MK II, he was sent to an adventurer's house to kill them, as they had been hampering with Jack's plans greatly. Arriving in a very large crate, when the adventurer investigated it, he burst out and attempted to kill them. However, he failed and his body was destroyed, leaving him as a decapitated head.
Knowing that Rabid Jack was responsible for this, the adventurer took his head to Mos Le'Harmless, where he was interrogated by the player and Bill Teach. Still refusing to reveal information, Bill suggested to subject him to the Twiblik Night Special, which was revealed to be makeup. Unable to withstand such "torture", he revealed where the Barrelchest MK IIs were being built. An outfit was made to allow the adventurer to infiltrate and destroy the facility, with his head being used to seal the deal; Bill ensured that his mouth was taped so that he could not reveal the adventurer. Bill kept him in custody after the event.
He was soon referred to as a "mutinous scum" by the other zombie pirates.
He later reappeared in Pieces of Hate, where Bill, several other captains, Madame Shih and the adventurer tried to find out where Jack's base of operations were. Since he had already given away vital information, he gave it to them under two conditions: finding a lifelong companion and appreciating culture, having come to peace with everything that happened.
The adventurer was tasked with satisfying his requests. Initially, he wanted a cat, so the adventurer went to Gertrude to try and get one for him. However, Gertrude had reserved them for other adventurers, and told them to talk to her kids. They revealed that they should try the lumber yard. Upon arriving and searching the area, they found a rat that had assisted them on Rock Island Prison. Both the head and the rat stared at each other for a moment. The head was delighted with the rat and had the adventurer create a collar so that he could "claim" it, which they did. The adventurer also brought him to the shores of Karajama so he could see the sunset, drinking three gnomish drinks. Satisfied with having a companion and appreciating culture, he told the group where Jack's base was.
After Jack was defeated by the adventurer, he later celebrates with the living pirates over their victory. It is unknown what happens to him afterwards.