Previously in Doom
The history of Doom is long and fascinating. However, most this information is unnecessary, as Doom 3 completely reboots the franchise. This latest edition is an upgrade to the 2004 release of Doom 3, so going in fresh is exactly what you want to do.
Learn more about Doom:

Back Story
The construction of Mars City has unearthed a set of alien artifacts and structures from an ancient Martian civilization. In 2104, archaeologists discover the Soul Cube along with tablets that describe teleportation technology. Scientists begin rebuilding the technology without realizing the portal will open a gate into Hell.

While players take on the role of an unnamed space marine, several important figures appear in the game. From scientists to military officers, the protagonist discovers the secrets of the alien race.

Doom is known for its guns. The BFG, along with most of the original armaments, reappear in Doom 3 BFG Edition. Some new ones, like the Machine Gun and the Soul Cube also join the mix. Drones and Sentry Bots also help players on occasion, giving some much needed back-up.
Notable Weapons

What would Doom 3 be without hordes of demons to blast back into hell. After all, the BFG 900 needs a target to work its bloody magic. Doom 3 BFG Edition features many monsters from the original game as well as a batch of new terrors that stalk the shadows.
Notable Monsters

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