Fan Casting DOOM

In a distant future, an unnamed space marine is posted to a dead-end assignment on Mars after assaulting his superior who ordered him and his unit to fire on Innocent civilians. The Union Aerospace Corporation accidentally opened up a physical portal and unleashed Hell on Mars. As the only surviving human soul, it's his duty to shoot those bastard intruders out of his sight, and finding a way out of this hellish invasion right back to Earth.