Scroll of Water Breathing

A consumable scroll granting underwater breathing for a number of seconds equal to the reader's Intelligence times three; doesn't protect against swimmer's ear or being eaten by an undead barracuda. Turns up in Carl's, Donut's, and Katia Grim's boss boxes alike, common enough on floor 5 that Mordecai reads it as a hint the floor is full of poison and water hazards.