Doom 3 has a huge, unofficial story expansion, and it's just been relaunched

Doom 3 is far from the best entry to the long-running FPS series, but a moody atmosphere, created by impressive lighting technology, still makes its Martian setting a compelling place to explore. It's also helped a group of modders called Team Future to use the game as the foundation for a sprawling expansion, Doom 3: Phobos, that adds a lengthy, unofficial story spin-off to the game well worth checking out. Now, as part of GOG's effort to streamline its users' ability to easily find and install mods, Phobos has been relaunched on the platform.

Team Future uses Doom 3 as the jumping off point for an expanded horror game that builds a whole new story from id Software's 2004 sequel. Set during the original game's events, it sees players assuming the role of an amnesiac character who finds themselves on Mars, wounded and attempting to piece together their past. The story unfolds through flashback sequences and, in the game's current timeline, with the player navigating the Martian invasion alongside an agent for a megacorporation.

Doom 3: Phobos takes place across four episodes. The first, Episode 1: Overdue, came out in 2018. Episode 2: Disruption followed in 2020, with Episode 3: Collapse arriving last June, 2024. The fourth and final episode hasn't launched yet.

The expansion not only features a new story, but also adds in totally original maps and enemies, updates for existing locations and monsters, and, most importantly for those disappointed by the weapon's original design in Doom 3, an improved shotgun.

Doom 3: Phobos is available for free, but it requires players to own Doom 3 and its Resurrection of Evil expansion to install. You can find more details or download it on GOG right here.

If you'd rather check out other games in Doom 3's wheelhouse, you can also find more options in our lists of the best FPS games and best old games on PC.

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