Dead Space 3
Publisher
Electronic Arts
C.M.S. Greeley side mission
After clearing out the ship, you will reach the end of the objective marker in a room with the gravity panels on either side, with a discharging electrical transformer. Collect the Electro Shot mod access the terminal in the final room. You can also find a circuit behind the door that requires a wrench.
Classic mode
Successfully complete the game. In this mode, only classic weapons through blueprints, there is no co-op mode, aiming is in the original style, and the difficulty setting is locked to hard.
Devil's Horns (Foam Finger Weapon)
Complete the game on Classic mode to unlock this weapon.
Hardcore mode
Successfully complete the game. In this mode, you will be sent to the start of the game any time you die.
Item Duplication (Cooperative Mode)
You can perform this cheat anywhere in the game, but it works best if you put it to use near a checkpoint and bench. You'll need to be playing with a friend, preferably one who is equipped with a headset so that you can communicate as needed. Start by giving your friend the items you wish to duplicate. After the trade is completed, exit out to the main menu and then immediately have the friend who received your loot save and quit from the pause menu. The trick only works if you follow that precise order, and quickly. If you did it properly, both players should now have the desired items in their inventory.