BFG-10000

In Doom Eternal, the BFG 10,000 is a massive defensive weapon on the Phobos moon base.

Trivia
The BFG 10K is a weapon found in Quake II and Quake Arena games. In Arena, it is one of the weapons Doom (character) has an affinity with.

It also appears in the Skulltag sourceport as a rapid fire BFG with a design similar to the BFG 9000 in the Doom movie.