Conversation so far:
What led to William II of England's downfall?
According to William of Malmesbury, William II of England was planning to invade the Duchy of Aquitaine at the time of his death.
What date did William II of England die on?
William II of England died on 2 August 1100.
Where did William II of England die?
William II of England died in the New Forest, probably near Brockenhurst.
What killed William II of England?
William II of England went hunting and was killed by an arrow.
Where did the arrow hit William II of England?
William II of England was killed by an arrow through the lung.
Who shot William II of England?
The earliest statement of the event was in the Anglo-Saxon Chronicle, which noted that William II of England was shot by an arrow by one of his own men.“
What does the other account besides the one in the Anglo-Saxon Chronicle say about who shot William II of England?
Later chroniclers added the name of the killer, although the description of events was later embroidered with other details that may or may not be true.

Question: What is his name?
Self-contained rewrite: What is the name of William II of England's killer?