There are guns, and then there are big f***ing guns.
Perhaps the most famous is the iconic B.F.G. from Doom. It starred in Doom back in the day, and it stars in Doom today. As a reminder, here it is, in action, in the new Doom.
Now, Doom's B.F.G. is real, sort of, via the magic of 3D printing.
Bethesda commissioned a 1:1 scale B.F.G. ("otherwise, what's the point? No one wants a LITTLE.F.G.") from MyMiniFactory, and had developer id Software share the B.F.G. in-game files so they could make it as accurate as possible. The creators broke the gun into over 70 smaller pieces that could be 3D-printed and then stuck together. It took around 1000 hours of pure 3D printing, with models being continuously printed across multiple printers for about a month.
The result is below. The 3D-printed B.F.G. is over three feet long, 18" in height, 18" in width and weighs 12kg. It's a beast.
Unfortunately you can't buy a real-life B.F.G. Bethesda gave the one model MyMiniFactory 3D-printed to a competition winner. Bah!