Far Cry 3 Episode 6: Piece of the Past

"Jason finds a hit man named Buck who is holding his friend Keith. In exchange for Keith, Buck wants the Asian ceremonial dagger, the same one that Citra needs."
"The ancient compass leads Jason to a Japanese WWII bunker. Inside, he finds his way to some old Chinese ruins, and retrieves another piece of the compass, though the knife still eludes him."