ManueraGum

Lifted from Phantasy Star II.

Manuera gum is manufacted from the leaves of the manuera bush, which grows naturally along the River of Tears north of Lookshy. A few Guild-affiliates operate plantations in the marshy, brackish land around the river, but the bush grows nowhere else in Creation.

Manuera gum smells of rotten eggs and attracts flies, but when chewed generates oxygen rapidly enough to fulfill a mortal's needs. It therefore enjoys great use by mariners all along the Inner Sea and rivermen in the Scavenger Lands, as it allows a user to operate underwater for hours without danger of drowning (although the gum does nothing to protect from the effects of pressure, temperature, or hostile sea beasts). Manuera gum spoils roughly six weeks after its manufacture, making it rare outside the vicinity of the River of Tears.

A lump of manuera gum good for four hours of oxygen generation is about the size of a golf ball, and is a Resources 2 purchase in the Scavenger Lands.