Serious Sam: The First Encounter (2001)

Sam "Serious" Stone, Earth's stud warrior, is sent back to Egypt, 3000 B.C., to fight hordes of alien monsters in this acclaimed "Doom"-sytle, back-to-basics, first-person shooter out of Croatia which is listed, amazingly, at the bargain basement price of 20 bucks! (metacritic.com)
Game Information
Genre: Shooter
Platforms: Windows, Linux, Xbox 360, PS2, Game Boy Advance, Xbox, GameCube
Franchise: Serious Sam
Developer: Croteam
Publishers: Devolver Digital, Gathering of Developers, 2K Play, Gotham Games