Prequel bonuses
Have a saved game file from the original Dead Space to begin the game with access to the Refurbished Plasma Cutter. However, your upgrades to the Plasma Cutter from Dead Space will not carry over.

Successfully complete Dead Space: Ignition in single player Ignition mode to unlock the Hacker Suit (has bonus perks and hacking capabilities), a Hacker-themed Contact Beam weapon skin, exclusive audio logs, and extra power nodes, health packs, and credits.

Hand Cannon
Successfully complete the game on the Hardcore difficulty to unlock the Hand Cannon at the first shop in a New Game+. The Hand Cannon is a powerful weapon with unlimited ammunition, is a foam finger, and Isaac says "Bang Bang" and "Pew Pew Pew" when shooting it.

Bonus suits
Successfully complete the game on any difficulty to unlock bonus elite suits in New Game+ mode. During a second playthrough, the Riot Armor Suit will be available in the store. The Elite Engineer Suit schematic can be found in Chapter 2 near the first store, just before the first short outer space section. The Elite Vintage Suit schematic can be found in Chapter 6 in the large hallway where Ellie and Stross are talking to you from the balcony and you are attacked by a Brute (it is next to a statue near the wall). The Elite Security Suit schematic can be found in Chapter 9 after exiting the tram with Ellie the first time; search over the railing to your right to find it on the floor. The Elite Advance Suit schematic can be found in Chapter 11 when the yellow lift that the Necromorphs jump onto reaches the top, turn around, and it is on the ledge between the elevator and wall.

Successfully complete the game on the Hardcore difficulty to unlock the Soldier Suit at the store. Successfully complete the game on the Zealot difficulty to unlock the Arctic Security Suit at the store.

Log into your same EA account through the Dead Space iOS game to unlock the Riot Armor Suit. This suit gives a weapon bonus to the Contact Beam of 10% extra damage and has 25 inventory slots and 25% armor.

New Game+ mode
Successfully complete the game on any difficulty to unlock New Game+ mode. This mode allows you to start a second playthrough with all your weapons, items, and inventory from the previous game.

Hardcore mode
Successfully complete the game on any difficulty to unlock the Hardcore difficulty. This difficulty is equivalent to the Zealot difficulty, but only allows you to restart from the last saved game. It also only allows you to save three times during the entire campaign, and cannot be started from a New Game +.

Re-spec ability
At the start of Chapter 7, you will have the option to re-spec your weapons, RIG, and stasis module. This ability allows you to take out all the power nodes in a piece of equipment and re-assign them elsewhere. Each time you re-spec an item, it will cost 5000 CR. This ability does not help you get the achievement for upgrading all your equipment, but it is helpful to re-assign (or take back) power nodes from weapons you do not use anymore. Additionally, you can use this ability to refill Isaac's health at any workbench. If you re-spec the RIG, any changes to a health node will reset Isaac's health to the new maximum. For 5,000 credits, a re-spec is cheaper than a large medikit.

Easy credits
Purchase the Supernova or Martial Law downloadable content. Then, go to the store, and purchase the Detonator weapon for free. Fire all the mines at a wall, then deactivate them and collect them. Do not reload the Detonator. Sell the mines and Detonator for credits at the store. Buy the Detonator back for free, and it will be fully stocked. Repeat this process as many times as desired.

Multiplayer unlockables
Reach the indicated level in Multiplayer mode to unlock the corresponding bonus:

Lurker Range Damage Increase: Level 3
Solid Army Green Suit: Level 4
Stasis Increase to 2 Shots: Level 5
Pack Melee Damage Increase: Level 6
Line Gun: Level 7
Solid Red Suit: Level 8
Spitter Execution Damage Increase: Level 9
Force Gun: Level 11
Puker Ranged Damage Increase: Level 12
Solid Black Suit: Level 13
Plasma Cutter Magazine Size Increase: Level 14
Lurker Melee Damage Increase: Level 15
Solid Olive Suit: Level 16
Seeker Rifle: Level 17
Pack Execution Attack Damage Increase: Level 18
Pulse Rifle Magazine Size Increase: Level 19
Urban Camo Blue Suit: Level 20
Spitter Melee Damage Increase: Level 21
Urban Camo Army Green Suit: Level 23
Puker Execution Attack Damage Increase: Level 24
Line Gun Magazine Size Increase: Level 25
Urban Camo Red Suit: Level 26
Lurker Execution Attack Damage Increase: Level 27
Javelin Gun: Level 28
Force Gun Magazine Size Increase: Level 29
Stasis Increase to 3 Shots: Level 30
Pack Health Increase: Level 31
Urban Camo Military: Level 32
Seeker Rifle Magazine Size Increase: Level 33
Plasma Cutter Weapon Damage Increase: Level 34
Spitter Ranged Damage Increase: Level 35
Urban Camo Olive Suit: Level 36
Pulse Rifle Weapon Damage Increase: Level 38
Puker Melee Damage Increase: Level 39
Rivet Gun Magazine Size Increase: Level 40
Tiger Camo Blue Suit: Level 41
Line Gun Weapon Damage Increase: Level 42
Lurker Health Increase: Level 43
Javelin Gun Magazine Size Increase: Level 44
Tiger Camo Army Green Suit: Level 45
Force Gun Weapon Damage Increase: Level 46
Pack Gets Out of Stasis Faster: Level 48
Tiger Camo Red Suit: Level 49
Seeker Rifle Damage Increase: Level 50
Tiger Camo Military Suit: Level 52
Spitter Health Increase: Level 53
Rivet Gun Weapon Damage Increase: Level 54
War Torn Suit: Level 56
Javelin Gun Weapon Damage Increase: Level 57
Puker Health Increase: Level 58
Visceral Games Suit: Level 59

Additionally, you can unlock the Solid Viral White Suit and Urban Camo Viral Yellow Suit by killing a player that is wearing them.

Schematic locations
Search the indicated locations to find all schematics:

Chapter 2
Power Node: It is in the first Power Node locked room you come across. You can open the locked door with a Power Node; you can find one on the ground through the door to the left of the closet.

Hacker Suit: It is at the end of the tram walkway area, near the spot you encounter the Fire Sack Necromorphs.

Stasis Pack: It is on the tracks by where the flaming train passes you for the first time.

Chapter 3
Pulse Rifle: Once you are out of the train, it is in a corner just behind where the train is hanging.

Javalin Spears: It is behind the big marker statue towards the windows on the left.

Chapter 4
Security Suit: It is on the top shelf of the room just past the door that you have to slow down to walk through.

Chapter 5
Ripper: In the multi level room, ride the elevator down, then go to the right side of the room to find it.

Medium Health Pack: After you turn off the gravity and go through the holes in the ceiling, you will find it floating in the middle of the room.

Line Gun Ammo: After crawling through the duct and falling, you will go through a storage room. You will find it behind some shelves on the right side.

Detonator: It is in a room at the top of the church by the save station.

Chapter 6
Seeker Rifle: On the path at the beginning of the chapter, take the door to the right. You will be on a balcony, and the schematic is on the far right side on the ground.

Pulse Rounds: When you first meet Ellie, she will unlock the gate. Instead of going through the gate behind her, follow the path around to the right where it is blocked by debris to find the schematic.

Flame Thrower: After you exit the gym, follow the path, and go into the classroom to find the "Kids Gone Crazy" text log. In that same room, there is a smaller room on the right side with blood on the wall. The schematic is on the ground.

Chapter 7
Ripper Blades: At the start of the chapter when you enter zero gravity, the schematic will be floating at the bottom of the room.

Force Gun: After you exit the elevator, turn left, and you will come across yellow lockers. The schematic in the second locker from the left.

Contact Beam: The schematic is in the locked closet to the left of the spot where you first see the save station on the wall. Use a Power Node to open the closet and get the schematic.

Chapter 8
Vintage Suit: The schematic is in the first locked door in this chapter.
Detonator Mines: When you first talk to Ellie and Stross, go to the next room, and take left. The schematic is beside a body.
Large Med Pack: The schematic is in the room where you first meet Ellie. It is past the table in the corner; you can move the table using your kinesis and grab it.

Chapter 9
Flame Fuel: When you come across the laser traps, take a right from where they were. You will come across a few crates lying around; use your kinesis to move the crates and find the schematic along with an audio log.

Seeker Shells: The schematic is behind the guardian mounted near the exit door of the room where you fight Stalkers and Cysts.

Chapter 10
Force Energy: When you reach the zero gravity area, go to the lower level to find the schematic on the ground.

Chapter 11
Contact Energy: In the zero gravity station where you move the lasers to gain access to the shaft that leads inside, you will find the schematic if you look outside from the inside of the shaft.

Advanced Suit: Enter the locked room opposite of the detonator mines trap. The schematic is inside this room, but you need a Power Node to open this locked room.

Hidden Necromorph messages
Use the Right Analog-stick to look around the following menu areas to find the following hidden messages:

Main menu
Upper left: "In the end, it all comes down to just one little thing..."
Bottom right: "Unity after death, unity forever."

Single Player menu
Upper left: "Your body now, our body later, one body forever"

Multiplayer menu
Upper middle: "It's not over between us, you can't run from me forever"
Bottom middle: "Make us Whole"

Quick Match menu
Bottom right: "We must believe in it and bend ourselves to its will and then it will heal us"

Leaderboard menu
Right: "The answer is in chicxulub"

Extra menu
Left: "Welcome back Nicole Brennan"

Controller Map menu
Bottom right: "Let us fear nothing. Death is only a transition to the unity beyond"

Easy "Collect Peng" achievement
In Chapter 7 (approximately halfway through the level), find the mainframe room where ANTI is located. One of the circuit rooms will have breakers that turn blue in addition to being green or red (it is the left breaker room, if ANTI's hologram emitters are behind Isaac). Insert the four breakers in that circuit room so they are blue, and the access tunnel will now lead to a new room with the Peng treasure.

Easy "Elevator Action" achievement
In Chapter 7, immediately after Isaac starts the elevator to go to the Solar Array area, a bunch of Tripods will appear. Use the Detonator to shoot them. Usually hitting a Tripod with the Detonator anywhere on the body will knock it off. Use Stasis to help hold a Tripod in place when more than one of them appears at a time. Knock off all Tripods in this sequence to get the "Elevator Action" achievement. If you do not get the achievement the first time, reload, and try again.

Easy "Lightspeed De Milo" achievement
Once you exit the elevator and enter the shopping center area after the train scene in Chapter 3, you will see a large statue rotating. Shoot the head off of it with any weapon to get the "Lightspeed De Milo" achievement.

Achievements
Accomplish the indicated achievement to get the corresponding number of Gamerscore points:

Mission Impossible (50 points): Complete the game on Zealot setting.
Romper Stomper (25 points): Stomp 10 Containers.
Vacuum Cleaner (30 points): Decompress 20 Necromorphs without getting sucked out yourself.
Made Us Whole (10 points): Complete the game on any difficulty setting.
Frozen in Time (10 points): Kill 50 Necromorphs while they are in Stasis (single player only).
First Aid (10 points): Use Quick Heal ten times (single player only).
Epic Dismemberment (50 points): Dismember 2,500 Necromorph Limbs (single player only).
...And Stay Down (10 points): Kill 25 crawling enemies with Stomp (single player only).
Think Fast (15 points): Kill 30 Necromorphs with Kinesis objects.
The Nanny (10 points): Kill 30 Crawlers without detonating them.
C-Section (10 points): Knock down an enemy with Contact Beam Alt-Fire then kill it with Primary Fire before it stands up.
Going for Distance (20 points): Impale an enemy and make him fly through the air for 17 meters - it must stick to the surface.
Taste of your own Medicine (20 points): TK Impale a live Slasher to a surface using a Slasher's arm - it must stick to the surface.
It's a Trap! (20 points): Kill 20 enemies with Detonator Mines in a deployed state.
Necro Flamb (10 points): Kill 50 enemies using the Flamethrower.
Peek a Boo! (20 points): Kill a Stalker with the Seeker Rifle while in Zoom Mode.
Brute Juke (10 points): Kill a Brute without taking damage.
Shoot the Limbs! (10 points): Dismember 25 Necromorph Limbs (single player only).
Bouncing Betty (10 points): Kill a Cyst by catching its Mine and throwing it back.
Skewered in Space (15 points): Impale an enemy into a Decompression Window to cause it to blow out.
Hard to the Core (50 points): Complete the game on Hard Core setting.
Clean Cut (10 points): Sever all three tentacles of a Lurker with one Line Gun Primary Fire shot (single player only).
Lawnmower Man (10 points): Kill 4 enemies with the same Ripper blade.
Fully Loaded (50 points): Simultaneously have four completely upgraded weapons.
The Sampler Platter (20 points): Kill a Necromorph with every Weapon in the game (single player only).
Lightspeed de Milo (10 points): Dismember the Lightspeed Boy Statue.
Looking good (10 points): Purchase the Advanced Suit.
Fully Outfitted (30 points): Upgrade your RIG and Stasis completely.
Picking favorites (30 points): Upgrade 1 Weapon completely.
The Engineer (10 points): Collect 10 Schematics.
My Boom Stick (20 points): Kill 6 enemies at once with Line Gun's Alt-Fire (single player only).
Shock Therapy (10 points): Impale an enemy with the Javelin Gun and use its Alt-Fire to shock 3 others (single player only).
Collect Peng (20 points): Find the Peng treasure.
The Librarian (10 points): Collect 100 logs.
The Electrician (10 points): Collect 10 Semiconductors.

Additionally, there are 15 secret achievements:

The Fugitive (50 points): Escape the Facility.
Cross your Heart, Hope to Die (30 points): Survive the Eye Poke Machine.
The Final Sacrifice (50 points): Destroy the Marker.
Clever Girls (10 points): Survive your first encounter with Stalkers.
Torment Me No More (20 points): Kill the Tormenter.
The Graduate (20 points): Win the fight at the School.
Patient on the Loose (15 points): Get your first Suit.
Derailed (20 points): Survive the Train Sequence.
One Small Step (10 points): Get through the first Zero-G area.
Hornet's Nest (30 points): Destroy the Tripod Nest.
Operation! (15 points): Snare the Shard with the Ishimura.
Knock Knock (25 points): Complete the Drill Ride.
Elevator Action (15 points): Knock off every Tripod during the Elevator Sequence.
Shut Down (10 points): Defeat the AI.
Powered Up (15 points): Complete the Solar Array Puzzle.

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