While shooting either the Crossbow or the Grenade Launcher, rapidly reload by pressing the left trigger, then quickly after pressing the right trigger. This allows you to start shooting without having to wait longer (several seconds) for your weapon to reload. This is especially useful against powerful enemies like Big Daddies.
Alcoholic beverages can be turned into Molotov cocktails by igniting them with a source of flame such as the Incinerate Plasmid or Chemical Thrower. Pick up the alcohol bottle with the Telekinesis Plasmid and throw it at a target.
Instead of buying health packs at health stations for $10, get them for free by smashing the machines with your wrench. After a couple hits, between 1-3 health packs should lie on the floor for you to grab, for free.
You will meet Sander Cohen about halfway through the game, a crazy artist dude. When you complete the level, you can just leave him or kill him. If you kill him at that point, you can't get one of the trophies; "Find Cohen's Room." A while later you will stumble onto Cohen's apartment. If he's alive, two Splicers will be dancing in the main room, with Cohen watching from his locked private room. Kill the Splicers and then Cohen comes out to fight you, thus unlocking the door and allowing you to earn the trophy.
Research the Houdini Splicers until you get the Natural Camouflage Tonic. If you have this equipped, you will become invisible if you remain still. This will protect you from Splicers, Big Daddies, and Bots if you set off an alarm. If you move again you will become visible. You cannot become invisible if an enemy sees you. If you are invisible and an enemy besides a Bot touches you, they will see you. The cameras and turrets also cannot see you if you are invisible.
1. In Peach Wilkins' hideout (Neptune's Bounty), bottom floor. As soon as you come downstairs it is directly in front of you.
2. On the way to Farmer's Market in Arcadia, the station is located to the left after you go up the first stairs coming from Tree Farm.
3. The Winery's basement in Farmer's Market. There is a flooded area with one of them attached to the wall. It is in front of you when you come down the stairs; just keep going forward.
4. In Fort Frolic, from the Atrium bottom floor, go towards the bathrooms. Then, move right and follow the path until you see some small stairs to your right leading up to a door. Go inside then go down into the basement. The basement is filled with cigars and the like. The upgrade station is on the wall.
5. Go to Poseidon Plaza in Fort Frolic. Go to the other end of the bottom floor (the opposite end of where you enter). Go into Sinclair Spirits (the room that has a corpse on a sort of "altar"). In the basement of this store is the station.
6. In Hephaestus Core Room, go down to the bottom floor and run around (literary). Eventually you will see it attached to the wall.
7. In Hephaestus, Kyburz's office. It is attached to the left wall (back turned to the entrance) in the rear of the room.
8. At the bottom floor of the Mercury Suites area, on the back of the center pillar.
9. In Sander Cohen's secret room, in the Olympus Heights' Mercury Suites area.
10. Go to Atlas' Headquarters in Apollo Square (Fontaine's Home For The Poor area). It is located on the fourth floor. Go down the stairs in the room and look to the right to find the station in front of you.
11. When you enter Point Prometheus and chase Fontaine, you will eventually end up in a little square and Fontaine will go behind a locked Museum door. At the opposite end of this square (from where you came) is a dead Big Daddy. Next to it is the upgrade.
12. In the Voice changing labs in Point Prometheus; one of the labs has it.
If you must fight a stationary security robot (RPG, etc.), use Telekenesis to grab a crate or pallet and hold it in front of you until you can find a place to hide and plan what to do next. The item you hold up will block some attacks.
The Chompers Dental key in the Medical Pavilion is acquired by using Telekinesis through the broken window to the left of the door. There is a corpse hanging over the broken window. The key must be grabbed with Telekinesis because it is hanging on a wall on the other side of the window. You can get Telekinesis in an area near here. You will need to get that first, but do not follow the arrow back to the rubble that you need to get rid of until exploring Chompers Dental. There is a safe and other good items to be found inside. Note that both Telekinesis and Chompers Dental are near where you find the shotgun.
The Hypnotize Big Daddy Plasmid and the Natural Camouflage Tonic are required for this trick. Simply use the Hypnotize Big Daddy Plasmid on a Big Daddy so that he thinks you're a Little Sister and protects you. Now here's the fun part; just find and attack another Big Daddy and your Big Daddy will attack it to protect you.
Temporarily disable security drones by using a blast of the Electric Shock Plasmid before you do anything else in a room. Then, run up to them within five seconds and hack them. You can hack while the game is on virtual "pause." You'll have security drones on your side for the rest of the time you are in a fight afterward.
After hacking a robot it will start firing at your enemies. If the robot gets hit it will begin to lose health, catch on fire, and eventually blow up. To stop this from happening, deactivate the robot (press A while pointing at the robot), then reactivate it a few seconds later. This will make the robot have full health again.
In Fontaine Fisheries, a Big Daddy and a Little Sister are behind a gate. You can either kill the Big Daddy later and come back for the Little Sister or you can kill the Big Daddy then use Telekinesis to drag his corpse over to the gate. When the Little Sister gets close enough (because they always stay near the corpse of a Big Daddy), you can rescue or harvest her through the gate.
After you become a Big Daddy, make a new saved game. You are near the end of the game. If you missed something you can go to the bathysphere and explore Rapture again. Also, you are a Big Daddy now so the splicers will not harm you, security cameras will not set off alarms, etc.
From the start you will have a wrench and the Electric Bolt Plasmid in your inventory. Using these in rapid succession against most Splicers can often result in an fast kill. First, shock the Splicer. Before the convulsion ends, switch out the wrench, aim high, and hit the Splicer over the head. However, best way to eliminate the agile Spider Splicers is to unleash a few clips of anti-personnel ammo, preferably from the machine gun.
Atlas Fontaine, the final Boss, has three different styles of attacks: Flame Plasmid Form, Ice Plasmid Form, and Electric Plasmid Form. The easiest way to defeat him during the first part is to use your Ice Plasmid and freeze him, then switch to your Telekinesis Plasmid. Grab an explosive tank and throw it at him. Also, if desired, just use your telekinesis. He is predictable if you are far away from him. Wait for him to throw a fire ball at you, then move out of the way. He will keep running past you; use this chance to fire the machine gun, which does the most damage to him. Once he goes back to his chamber to gain his life back, change to the Flame Plasmid and get ready for some bots. Once he starts his routine of fire and run, blast again him with the Flame Plasmid . The more you blast him, the faster he loses life. Continue to use the machine gun while he is aflame. He will now go back to his chamber one last time and then have electrical powers. Keep your Flame Plasmid ready. This time, shoot him with the Flame Plasmid and he will run for the water. Once he jumps in the water and comes back out, hit him with it again. Be aware that there are splicers around. Also set them ablaze to get some extra life. There are many different ways to defeat him but this seemed to be the easiest.
The easiest way to defeat Atlas is to have the fully upgraded shotgun and the Decoy ability. After you drain his Adam, drop a decoy and, while Atlas is attacking it, use the shot gun. After you have used all four rounds, quickly cast Decoy again, reload your shotgun, then begin shooting him again. Repeat this until you have to drain his Adam. Once again, reload your shotgun and Plasmids before you drain his Adam, then start over using Decoy and the shotgun. Use Health Packs as needed and ignore any Splicers in the area as they will be paying attention to your Decoy just like Atlas.
After getting the camera and Hypnotize Big Daddy tonic, find a Big Daddy and follow him until he walks up to one of the wall vents. If you haven't already saved or harvested the Little Sister, he will hit the wall and one will crawl out. Take as many pictures as you can until you can't get any more research, then use Hypnotize Big Daddy. The Little Sister will crawl back into the vent. After Hypnotize wears off, the Big Daddy will hit the wall again, bringing out another Little Sister. Repeat the process to unlock the trophy.
Don't harvest a single Little Sister as you play the game. Tenebaum will reward you with gifts (and Adam) every time you rescue three Little Sisters. This is better since you get the same amount of Adam as you would if you harvested them but you also get the trophy hint.
Don't kill Cohen after completing his "masterpiece". When you go to the Olympus Heights and get to the area with multiple levels (not Fontaine's house for the poor) to get the second half of the antidote, visit one of the apartments on the first level (to your right from the entrance). This is Cohen's apartment. When he tells you not the disturb the dancers, "knock over" the record player and deal with the upset duo. Cohen himself will then come down to kill you. He can be taken out then. Go upstairs in his apartment (the door to your right upon entering his place) to receive the trophy for entering his apartment and reaching a Power To The People machine. Now, Sander Cohen will not stay dead. Pickpocket his corpse for his Muse key. When you get back on the Bathysphere, go to Fort Frolic and access the Muse (the chained up display) for some decent items, especially if you need first aid kits. Using your chemical thrower (and perhaps anything else), walk to the "masterpiece" and add Napalm and Criticism together, then torch the awful thing. The area will turn red and Cohen will appear for round two. He is a little tougher to kill this time and fights like a Houdini splicer. Pickpocket him again for the same items as last time (including the key for the already opened Muse). He is now permanently dead.
When you first enter the room, hit him with the tool the Little Sisters gave you and fight him when he throws you off. Once he is back on the bed, run up and hit him again with the tool to drain his Adam. This works much faster due to him only have four or five jars of Adam to drain, and the fights are not very long afterwards.
When buying Plasmids, Tonics, and Upgrades from the Gatherer's Garden, make sure to buy the Tonics first. Then, search every area for other Tonics. When you reach Point Prometheus there will be three Tonics to find, while the rest of the Tonics are available in the Gatherer's Garden. This will ensure you get the trophies. Note: To check how many Tonics you have, go to a Gene Bank and count each "track".
In the Arcadia level you will find a place that appears to be a bar. Look around a bit and you will see a block of cheese followed by holes. The cheese is cut like Pac-Man himself and there are holes next to it, none of which can be gun shots. If you shoot the floor with any weapon you have, the marks will not match.
After obtaining the crossbow and at least five Trap Bolts, it is easy to take down a Big Daddy. Face a wall and stand about three feet away. Make sure it is not something that the bolts can bounce off of, and also make sure you have a good ten foot long straight wall. Once you are better skilled at this technique you can try for shorter lengths if desired. Point straight ahead and fire out a bolt before taking about two steps to the left or right, depending on which way the Bid Daddy is and your location, and fire another. Fire all five bolts out, then shoot the Big Daddy once with anything. If done correctly, it will run through the line of traps, taking enough health down so he can be killed with a few shots of any other weapon. Note: This may not work in an open area because Big Daddies strafe often. If you have the damage increase for the crossbow, it will only take three or four bolts to kill him. Do not crouch while setting up the traps. If the Big Daddy walks another way and gets out of sight, you might need to go back to get him. If you do get him, you can crouch under the set traps. An easy way to trigger bolt traps is to pick up something with Telekinesis and drag the object through it.
Get your shotgun fully upgraded (power to the people stations, rate of fire, and damage upgrades) and simply use your old 00 buck. After killing them, get the Little Sister and all the money they had on them. This can result to very little damage from Big Daddies. Aim for the head to cause more damage. Note: This was done under the Easy difficulty setting.
After acquiring the Security Bullseye Plasmid, set off an alarm either by hacking or being spotted by a security camera, then throw the Security Bullseye at the Big Daddy. You may have to do this twice depending on how much health the Big Daddy has when starting out. Try to avoid the battle because the crossfire and exploding bots will damage you. The only problem with this technique is that once the Big Daddy is taken down, the bots will come after you. Be prepared to either run and hide, or fight them off.
Usually, Little Sisters will return to the same corpses several times. You can use this to your advantage by placing the corpse near a security camera with the Telekinisis plasmid, then wait for her to show up and tag her Big Daddy with the Security plasmid. He will keep returning if he survives. You can stay in the same safe location and wait for the bots to finish off the Big Daddy.
Just use two Trap Bolts in Poseidon. If you get the damage increase for the crossbow, aim for the face.
When fighting a Rosie, use armor piercing rounds with the machine gun or pistol. Another effective way of killing them is by launching frag grenades and running out a door. The Rosie will follow you, fire proximity mines at the door, and be damaged or destroyed when it walks through it will.
While in levels that have more than one Little Sister in them, there are sometimes Rosies roaming the level alone. The following only happens if you have already harvested or saved at least one but not all the Little Sisters in that level. The lone Rosie will walk up to one of the many holes in the walls through which the girls crawl through and bang on the metal before waiting. Then, it will help a Little Sister jump down from the opening. The girl will then lead the Rosie throughout the level. Therefore, when hunting these formidable enemies, do not attack or ignore a Rosie if it walks alone (as long as in the pause screen it says that there is still at least one Little Sister remaining). Rather, follow it and wait for it to summon a Little Sister out of the wall, then attack it using whatever strategy suits you. If you attack it when it's alone you will not get to harvest or save any Little Sister as a reward for killing it.
Reach the end of the game under the or Normal difficulty and bring Atlas down to his last jar of Adam. Then, pause game play, go to the "Options" menu, and change the difficulty to "Hard". Defeat Atlas to unlock the trophies. Note: You cannot die while unlocking the "Brass Balls" trophy.
Immediately after receiving The ADOM extractor from the Little Sister, do not take the elevator to the last fight. Instead, go through the rooms you missed along the way. Turrets, Splicers, cameras, and Big Daddies will not see you, and electric trap bolts will not hurt
While using the Telekinesis Plasmid, it is possible to drop the item you are holding instead of throwing it across the room. To do this you must have an item currently being held. Pick up any item with the Telekinesis Plasmid selected. Using the LT button, keep holding the item, and don’t let go of the LT button. When you’re ready to drop the item, press the RB button to open your weapons menu and, in the transition of the weapons menu opening, let go of the LT button. Select your weapon and the item will drop safely to your feet. If done correctly, the item falls at your feet, instead of being thrown, which makes the item easier to find when you need it. A simpler way to drop the item you're holding is to just hit 'X'. So, with the Telekinesis Plasmid armed, hold LT to TK something to you. While it is 'in your face', press X to drop it on the ground--with no need to switch to weapons.
When the dark cloud envelopes the icy battlefield where you face Peach Wilkins, save the game and locate the hostile turret at the end of the room when the cloud clears. Load the game and run to it before the cloud clears so you can quickly freeze or shock it, then hack it so it shoots your enemies. Crouch down by the area to your right when facing the turret. There are some barriers here to protect you from enemy fire. However, to avoid damage by Wilkins' grenades, keep Telekinesis as your active Plasmid. He will avoid the turret's fire, but as long as you stay behind the barriers by the turret, he will stay at a safe distance. This gives you time to calmly return his grenades using Telekinesis until he is dead. The turret will take out most of the Splicers. This method makes things much easier because it eliminates the hectic "run around and whack people with the wrench" strategy that is your only other option. That turret, if not used as an ally, would probably be the main cause of your death, along with the bots triggered by the security camera. However, by hiding near the allied turret, you also hide from the camera's view.