|The following is based on content from Fallout: New California and has not been confirmed by canon sources.|
While in a fight, the harpoon gun generates one reroll if the player character has Perception. As a ranged weapon, it allows the player character to attack enemies one space away from them. While attacking an enemy with the harpoon gun, that enemy cannot make use of the retreat or armor abilities.
The harpoon gun can be obtained through the shop.