To get Isaac's Classic Engineering Suit from Dead Space 1, you have to finish the game once on any difficulty level.
Comms Circuit Set
Find all in-game 36 Audio Logs in the game.
First Contact Outfit
Included with the Limited Edition version of the game, in the "First Contact Pack".
Flight Suit
To unlock the Flight Suit, find all 40 Artifacts in the game.
Hostile Environment Outfit
To get the Hostile Environment Suit, you have to complete all 10 Optional Missions in the game's co-op mode, so that Carver's side missions are included as well.
MK-II Overclocked Frame Set
To unlock this frame set you must succesfully complete all 10 Optional Missions and also complete the Carver's Side Missions in the game's co-op mode.
Planet Cracker Plasma Cutter
For this you need a saved file from the game "Dead Space 2". Use it to unlock Planet Cracker Plasma Cutter for this game.
Research Circuit Set
Find all in-game 35 Text logs in the game.
Witness Suit
Included with the Limited Edition version of the game, in the "Witness The Truth Pack".
