Mass Effect 2 & Mass Effect 3
A so-called "super Earth," Volturno is home to organic life but is nevertheless uninhabitable for the near future. Currently in an Ice Age, most of the planet from the latitude of 30 degrees north or south is a frozen wasteland, and so most organic life, limited to algae and lichens, resides near the equator. The strong gravity prevents any sapient species but elcor from thriving on the planet, and the elcor cannot breathe the planet's atmosphere, which contains lethal amounts of carbon dioxide in addition to its oxygen. Small packs of vorcha squatters are attempting to take the planet for themselves illegally, but most of them live miserable existences in the planet's crushing gravity and die from falls and medical complications. Only terraforming on a massive scale would turn Volturno into a habitable world, and the elcor lack the political capital with the Citadel Council to begin such an effort.