Almas

Almas is the fourth and outermost planet in the Cularin system. Over a thousand years ago, a plant named kaluthin took root on the icy, lifeless world, nourishing itself from large underground lakes. Over time, the kaluthin synthesized the planet’s poisonous atmosphere (composed in large part of methane and phosphorus) into enough oxygen to sustain carbon-based life.
Still, prolonged exposure can be hazardous to one's health due to trace amounts of toxins, and breath masks or atmospheric regulators are strongly recommended.