There are no more cheats in games, and even if there are, they're the kind you generally have to pay for as a paid service, or hack the game with a trainer you download from some illicit website.
Gone are the days of the Konami Code, as games now come with achievements and unlocks and a host of online and social functions that any real and proper cheat would only serve as a wrench in the works.
The term "cheats" now pertains to anything that might help your game a little bit easier, as a way to skirt the rules and to play the game in ways the designers may have never intended. That being said, games aren't without their exploits, and tricks to help you gain an edge over your opponents be they real or virtual (as in, they're monsters in the game that you have to kill).
With that in mind, here are some cheats for Dead Space 3 that'll help you on your way to turning Isaac Clarke into a lean mean killing machine with the best damn weapons at his disposal. Barring that, it'll at least help you to survive the game's harder difficulty levels.
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Dead Space 3 Glitches | Exploits: Infinite Item Respawn, Unlimited Resources and More
Dead Space 3 Achievements | Secret Achievements
Dead Space 3 - Under a Buck Achievement
Dead Space 3 Unlock Devil's Horn's - Hand Cannon - Best Gun in Game
Dead Space 3 All Suits
Dead Space 3 All Unlockables
Dead Space 3 complete the game on hardest to unlock retro mode
Unlock the N7 Armor by having a Mass Effect 3 save game profile on your console.