| Before | After |

Explore the 'Before and After' aspects of Doom 3, detailing changes from the original game and key features of the id Tech 4 engine. Learn about gameplay, weapons, and enemies.

This section details the 'Before and After' aspects of Doom 3, focusing on its development, features, and gameplay evolution. It covers the game's setting on Mars in 2145, the player's role as an unnamed Marine fighting demonic hordes, and the technological advancements of the id Tech 4 engine, including unified lighting and shadowing.

The guide also touches upon the game's release for various platforms, including Windows, Linux, Mac OS X, and Xbox, as well as its expansion, Doom 3: Resurrection of Evil. It highlights key gameplay features, weapon systems, enemy types, and the overall plot, contrasting it with the original Doom.