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

Rank 1
Weapon: Pistol/Shotgun
Plasmid: Electro Bol/Winter Blast/Incinerate
Mask: Rabbit/Goat/Pink Feather
Melee: Wrench/Candle Stick/Pipe

Rank 2
Weapon: Machine Gun

Rank 3
Tonic: Expert Researcher/Security Evasion

Rank 4
Plasmid: Air Dash

Rank 5
Upgrade: Pistol Automatic Firing

Rank 6
Weapon: Grenade Launcher

Rank 7
Tonic: Speedy Recovery/Eve Saver

Rank 8
Plasmid: Geyser Trap

Rank 9
Upgrade: Shotgun Rate of Fire

Rank 10
Weapon: Crossbow
Mask: Eagle/Tragic Comedy
Melee: Machete/Rolling Pin

Rank 11
Tonic: Back Stabber

Rank 12
Plasmid: Telekinesis

Rank 13
Upgrade: Machine Gun Magazine Size

Rank 14
Weapon: Nail Gun

Rank 15
Tonic: Metabolic Eve

Rank 16
Plasmid: Houdini

Rank 17
Upgrade: Grenade Launcher Homing Grenades

Rank 18
Weapon: Elephant Gun

Rank 19
Tonic: Sabotage

Rank 20
Plasmid: Insect Swarm
Mask: Moon/Indigo Feather
Melee: Mallet/Barbed Wire

Rank 21
Upgrade: Crossbow Damage Increase

Rank 22
Tonic: Repairman

Rank 23
Upgrade: Nail Gun Magazine Size

Rank 24
Upgrade: Speedy Hacker

Rank 25
Upgrade: Elephant Gun Sniper Scope

Rank 26
Tonic: Slugger

Rank 27
Upgrade: Pistol Damage Upgrade

Rank 28
Tonic: Leg Up

Rank 29
Upgrade: Shotgun Automatic Reload

Rank 30
Tonic: Fast Feet
Mask: Peacock Feather/Sun God
Melee: Crowbar/Flashlight

Rank 31
Upgrade: Machine Gun Kickback Reduction

Rank 32
Tonic: Deadly Machine

Rank 33
Upgrade: Grenade Launcher Velocity Boost

Rank 34
Tonic: Headhunter

Rank 35
Upgrade: Crossbow Rate of Fire

Rank 36
Tonic: Big Game Hunter

Rank 37
Upgrade: Nail Gun Damage Increase

Rank 38
Tonic: Death Trap

Rank 39
Upgrade: Elephant Gun Damage Increase

Rank 40
Tonic: Resurrection
Mask: Octopus/Demon
Melee: Hatchet

Door codes
Enter the indicated code to open the corresponding door:

Adonis Luxury Resort
Door near rubble with code written backwards on glass: "1540"

Pauper's Drop
The Clinic: "0047"

Siren Alley
Maintenance Area: "1919"

Dionysus Park
Power To The People weapon upgrade station door: "1080"
Fontaine Futuristics
Plasmid Theater: "5254"

Inner Persephone
Watch Tower: "2673"
Recreational Therapy: "4146"

Easy health
Melee a health station, and a health kit will come out.

Easy money
Find an area that contains a working slot machine. For example, in the Siren Alley level inside the Mermaids Lounge, go upstairs into the room on the right side of the balcony that contains the slot machines. As you enter the room, turn left, and play the right-hand machine of the two that are facing you. Save the game before you start, and resave it every time your total money increases above where you started. If the machine does not payout after about a dozen turns, reload your saved game. It is possible to max out your wallet in approximately ten minutes. Repeat this as many times as desired.

Easy Security research
Find a hackable vending or health machine next to or near a Bot Shutdown Panel. Hack the machine, and stop the pointer on the red to activate the alarm, thus triggering the Security Bots to come after you. Once you see them, quickly take a picture of one of them with the camera, then use the Bot Shutdown Panel to shut them down. The disabled bot will still be highlighted by the research camera, allowing you to research Security easily.

Easy XP in Multiplayer mode
Have a friend join your game while it is in progress on any team-based game, putting him or her on the other team. Find a turret anywhere in the map, and make sure there is nobody around. You and your friend can hack the turret back and forth for 10 XP per hack. Repeat this as many times as desired.

Alternate endings
Successfully complete the indicated tasks to get the corresponding ending. There are six different endings: Rise To Surface (good and evil), Abandoned (good and evil), and the standard ending (good and evil).

Good endings
Save all Little Sisters you adopt, and spare Grace Holloway, Stanley Poole, or Gilbert Alexander.

Standard endings
Save at least one Little Sister, and harvest at least one Little Sister. Choose to die at the end, and spare Grace Holloway, Stanley Poole, and Gilbert Alexander.

Bad endings
Save at least one Little Sister, and harvest at least one Little Sister. Choose to live at the end, and spare Grace Holloway, Stanley Poole, and Gilbert Alexander. Alternately, harvest all Little Sisters you adopt, and spare Grace Holloway, Stanley Poole, and Gilbert Alexander.

Free Telekinesis
Use the following trick to pull normal items toward you with Telekinesis and not use any Eve. Eve is only used when you release the button to throw an item with Telekinesis. Use Telekinesis to pull items such as ammunition or first aid kits toward you to collect without wasting any of your Eve. If you take an item you are already maxed out of, you will either be stuck holding it with Telekinesis or have to release the button to throw it and use some Eve. However, if you display the Plasmid wheel and select another Plasmid attack, you can release the button to drop the item without Telekinesis automatically throwing it. Thus, you will not use any Eve by dropping an item you cannot carry. This can also be used when pulling electrified trip wires out of walls. To do this, pull the item toward you with Telekinesis, and without releasing the trigger, display the Plasmid wheel to select another plasmid. When you close the Plasmid wheel and release the trigger, you will drop the item.

Defeating Rumblers
When fighting a Rumbler (Big Daddy with rockets), use Telekinesis to grab the rockets it fires and throw them back at it.

Power To The People weapon upgrade station locations
Power To The People weapon upgrade stations can be found at the following locations:

1. Ryan Amusements: Going to get the ticket.
2. Ryan Amusements: After the family display, through the door.
3. Pauper's Drop: From Journal 039, go out the door, down the stairs.
4. Pauper's Drop: In the back of skid row, in the limbo room. It is behind the stage
5. Pauper's Drop: After breaking into the hotel, when you are going through the halls, you will go through a hole. To the left is a blue sheet. To the right is the station.
6. Siren Alley: In Mermaid Lounge, go upstairs, and hack the gate. Then, drop through a hole in the floor.
7. Siren Alley: Just before Pump Station 5.
8. Dionysus Park: Behind the door; combination is "1080".
9. Dionysus Park: On the path to the train.
10. Fontaine Futuristics: After you destroy the flying Gil bot, you can enter where you gain access to the laboratory.
11. Fontaine Futuristics: After you turn on the lights, it will be in the bottom of the holding cells area.
12. Persephone Outer: On your left.
13. Inner Persephone: After you gain access to Sinclair, look back in the room.
14. Inner Persephone: Just after Ward B in the room with the rocket turret.

Easy "9-Irony" trophy

After you get your first Little Sister in Ryan Amusements, she will take you back into the main hall of Ryan Amusements to collect ADAM. While she is collecting ADAM, Splicers will attack, breaking down the door to the next part of the level. After going through the door, there will be a desk on the left with an animatronic Andrew Ryan sitting behind it, and near a cabinet behind him is a golf club. Use Telekinesis to pick up the club, then shoot it at the Andrew Ryan animatronic to get the "9-Irony" trophy.

Trophies
Successfully complete one of the following tasks to get a trophy:

Bought a Slot (Bronze): Bought one Plasmid or Tonic Slot at a Gatherer's Garden.
Max Plasmid Slots (Bronze): Fully upgraded to the maximum number of Plasmid Slots.
Upgraded a Weapon (Bronze): Upgraded a weapon at a Power to the People Station.
Fully Upgraded a Weapon (Bronze): Installed the third upgrade to a weapon.
All Weapon Upgrades (Bronze): Found every Power to the People weapon upgrade in the game.
Prolific Hacker (Bronze): Hacked one of each kind of machine.
Master hacker (Bronze): Hacked 30 machines at a distance with the Hack Tool.
First Research (Bronze): Researched a Splicer with the Research Camera.
One Research Track (Bronze): Maxed out one Research Track.
Research Master (Bronze): Completed all research on every subject in Rapture.
Fully Upgraded a Plasmid (Bronze): Fully upgraded one Plasmid to the Level 3 version.
All Plasmids (Bronze): Found or purchased all 11 basic Plasmid types.
Trap Master (Bronze): Killed 30 enemies using only Traps.
Master Protector (Bronze): Got through a Gather with no damage and no one getting to the Little Sister.
Big Spender (Bronze): Spent 2000 dollars at Vending Machines.
Welcome to Rapture (Bronze): Completed your first non-private match.
Unnatural Selection (Bronze): Scored your first kill in a non-private match.
Disgusting Frankenstein (Bronze): Become a Big Daddy for the first time in a non-private match.
"Mr. Bubbles - No!" (Bronze): Took down your first Big Daddy in a non-private match.
Against All Odds (Bronze): Finished the game on the hardest difficulty level.
Two-Bit Heroics (Bronze): Complete your first trial in a non-private match.
Mother Goose (Bronze): Saved your first Little Sister in a non-private match.
Parasite (Bronze): Achieved Rank 10.
Little Moth (Bronze): Achieved Rank 20.
Skin Job (Bronze): Achieved Rank 30.
Man About Town (Bronze): Played at least one non-private match on each multiplayer map.
Grand Daddy (Silver): Defeated 3 Big Daddies without dying during the fight.
Master Gatherer (Silver): Gathered 600 ADAM with Little Sisters.
Dealt with Every Little Sister (Silver): Dealt with every Little Sister.
Big Brass Balls (Silver): Finished the game without using Vita-Chambers.
Rapture Historian (Silver): Found 100 audio diaries.
Proving Grounds (Silver): Won your first non-private match.
Choose the Impossible (Gold): Achieve Rank 40.
Platinum (Platinum): Unlocked all trophies.

Additionally, there are seventeen secret trophies:

Daddy's Home (Bronze): Found your way back into the ruins of Rapture.
Protector (Bronze): Defended yourself against Lamb's assault in the train station.
Sinclair’s Solution (Bronze): Joined forces with Sinclair in Ryan Amusements.
Confronted Grace (Bronze): Confronted Lamb’s lieutenant in Pauper’s Drop.
Defeated the Preacher (Bronze): Defeated the Preacher.
Nose for News (Bronze): Uncovered the secret of Dionysus Park.
Found Lamb's Hideout (Bronze): Gained access to Lamb’s stronghold.
Reunion (Bronze): Reunited with your original Little Sister.
Heading to the Surface (Bronze): Headed to the surface on the side of Sinclair's escape pod.
Escape (Gold): Escaped Rapture.
9-Irony (Bronze): Paid your respects to the founder of Rapture.
Distance Hacker (Bronze): Used the Hack Tool to hack an object at a distance.
Unbreakable (Bronze): Defended yourself against the Big Sister without dying.
Look at You, Hacker (Bronze): Killed 50 enemies using only hacked Security.
Adopted a Little Sister (Bronze): Adopted a new Little Sister for the first time.
Savior (Silver): Saved every Little Sister and spared Grace, Stanley and Gil.
Counterattack (Bronze): Killed an enemy with its own projectile.

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