Altitude Fern

This evergreen has soft green leaves and sprouts fronds laden with unusual sky-blue berries. When ingested, these waxy berries grant the imbiber immunity to all effects caused by high altitude. They do not grant immunity to damage from extreme temperatures, nor do they grant the ability to survive without air. The effects of a berry last for 1 day. An altitude fern produces up to six berries a day, and it bears no more than 50 berries at a time.