And luckily for PlayStation Plus subscribers, this gem is free to claim all month long. Taking place a handful of years after the events of 2011’s Warhammer 40,000: Space Marine, Boltgun recounts the aftermath of Captain Titus’ campaign on the forgeworld of Graia. It’s pretty fortuitous that the game is free on PlayStation Plus the same month as id Software’s latest game, Doom: The Dark Ages. It’s also the perfect excuse to jump into Space Marine 2. It’s a fantastic shooter well worth adding to your PlayStation Plus library.