The Harpoon is the replacement of the Spear Gun, From Bioshock 2. It Comes in the Zeus's Bolt DLC Pack. It is only avilable in Zeus's Bolt For Omicron to use and In Rapture Explorer Mode for Jason.
Spear: Normal Ammo for Harpoon
Exploding Spear: Replaces the rocket Spear, Sticks and Blows up on Enemies. The Rocket spear is unrealistic ask y in Comments
Stactic Spear: Shocks and Stuns enemies For 5 seconds And Does 10-20 Damage.
Upgrade 1: Scope- Adds a Zoom Increase to the Harpoon
Upgrade 2: Damage Increase- Adds +10 damge to the Harpoon
Upgrade 3: Speed upgrade- Faster Firing and Reloading