Giro Pakil Gideon from Enga Province pleaded guilty to cutting a Peter Aki using a bush knife in the early hours of October 3, 2015 at Makana, Nine-Mile.
He told the court he cut Aki after the victim told him that he was the man responsible for the death of his step father.
The two were in the company of others the previous night drinking when Aki told Gideon he killed his father.
Gideon then took his revenge and cut Aki in his sleep.
The court heard he sat on Aki’s legs and slashed his head four times, leaving four deep wounds.