Shadowgrounds Survivor is a shooter game developed by Frozenbyte and the sequel to Shadowgrounds. It has three playable characters, a RPG-like upgrade system for weapons and characters, a survival mode, graphics enhanced from its predecessor, an integrated physics engine, and a soundtrack by Ari Pulkkinen. Shadowgrounds Survivor tells the story of three survivors who join forces with the last remaining human resistance in the heated battle against the ongoing alien onslaught.
Frozenbyte announced a port of the game to Linux on March 13, 2008. The finished port, which was made by IGIOS and published by Linux Game Publishing, was released on September 18, 2009.
Source: Wikipedia, "Shadowgrounds Survivor", available under the CC-BY-SA License.