From Compendium of Worldly Lore
Needs review
Source: Stormwrack
Description: You have developed the technique of firing a ranged weapon into or through the water with better accuracy than normal.
Prerequisites: Point Blank Shot
You can employ ranged weapons underwater at a reduced range increment. You do not take the normal penalty for making a ranged attack through water.
Thrown Weapons: You can use thrown piercing weapons underwater with a –2 penalty for every 5 feet of water passed through, in addition to any range increment penalties.
Missile Weapons: You can use bows and crossbows underwater with a –2 penalty for every 10 feet of water passed through, in addition to any range increment penalties.
Aquatic Longbow: You can fire an aquatic longbow underwater with a range increment of 30 feet In addition, water does not provide any cover against your ranged attacks if you are out of the water and firing at a target in the water.
If your weapon’s range increment is different underwater than it is above the water, count the water surface as the beginning of a new range increment, and use your underwater range increment after the point at which your weapon strikes the water.