Basic Rules, pg. 188
Potion of Waterbreathing
Potion
Uncommon
Harvesting
Raw Materials:
Aboleth Mucus (1 vial)
Harvestable from Aboleths
Craftsmen:
Alchemist
You can breathe underwater for 1 hour after drinking this potion. Its cloudy green fluid smells of the sea and has a jellyfish-like bubble floating in it.
Cost: 400 gp