Destroyer of Worlds: Alien RPG - Rules of Play says:
Destroyer of Worlds is a complete Cinematic Scenario for the ALIEN roleplaying game, written by sci-fi novelist Andrew E.C. Gaska just like Chariot of the Gods. In Destroyer of Worlds, players take the roles of Colonial Marines. The scenario is designed for 3–5 players plus the Game Mother, and it’s a gauntlet of one hell after another. Expect it to take three sessions to complete.