Here's a fun one to start your week off right. Modder Carl Asami has combined the worlds of Fallout with DOOM for you to blast through. Originally released back in January, the modder has continued improving it since release. You even get your own Dogmeat companion that will fight along side you.
From the Mod DB page:
War. War never changes. And neither does-
THE DOOM DWELLER- you were chosen by THE OVERSEER to enter VAULT 666 and locate THE WATER CHIP. If you fail, your home, your friends, and your PET BUNNY will perish.
Traveling the Wasteland, your investigations lead you to a CAVE ENTRANCE. But what's this? No vault dwellers in sight, but more mutants than you can shake a boomstick at! It stinks like rotten meat!
So, pump that POWER FIST, rev that RIPPER, and unload your 10MM, right into the face of HELL! Welcome to VAULT 666!
Death in the Vault is about to change!

Direct Link
Check it out on Mod DB.
You can play it on Linux with the cross-platform GZDoom project.
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