|For a cross-game overview of this perk, see Aquaboy.|
“Water is your ally. The Commonwealth has an impressive amount of it. Whether you're swimming the lakes or exploring the depths of the ocean, having the ability to use stealth and not suffer any ill effects from water is a most impressive feat indeed. It allows escape in any direction and sneak attacks on shoreline strongholds.”— Fallout 4 Vault Dweller's Survival Guide description
The first rank of this perk grants the Sole Survivor the ability to swim in any body of water without receiving radiation damage, it also allows for underwater breathing. With the second rank, they become undetectable while being submerged.
|1||END 5||Water is your ally. You no longer take radiation damage from swimming, and can breathe underwater.||000E9453 (Aquagirl)|
|2||END 5, LVL 21||You become totally undetectable while submerged.||001D248E (Aquagirl)|
- While underwater, weapons cannot be equipped, and the Pip-Boy light does not illuminate a very large area.
- The benefits of the first level of this perk can also be obtained by eating mirelurk cakes and using items or equipment to boost Radiation Resistance.
- This perk may be useful while exploring some of the many 10+ Rads areas at the beginning of the game when items that provide Radiation Resistance are scarce. There are also plenty of sunken locations throughout the Commonwealth and Far Harbor, in addition to scrappable underwater materials such as concrete near workshops.
- There are at least three missions involving being underwater for an extended period of time: Pull the Plug, Here There Be Monsters and Clean the Water Supply.