A plasmid is a Adam-derived serum that rewrites your genome to give you specific powers. Plasmids are active: You must choose which plasmid to use and when to use it. Gene tonics, in contrast, are passive, working in the background.
Upgrades to plasmids become a must on the later levels, as aggressors and other enemies become tougher and current plasmids become less effective. They are available even if you do not pick up the original versions.
Upgrade? Yes (++)
You become a walking generator with this very first plasmid. You can zap enemies stupid for a few seconds, letting you get in some hits. In fact Atlas teaches you how to use this sort of attack: Zap 'em, then whack 'em. The one-two punch!
You can zap enemies in pools of water, killing multiple aggressors and seriously weakening Big Daddies. You can also zap security cameras, bots and turrets, giving you time to hack or destroy them. And you can zap shorted-out levers to open doors. You can blast off locks and chains from afar; but that is something to avoid as a habit (instead, use the wrench or shoot them) because, even with the Eve Saver tonic, the Electro Bolt is thirsty for Eve.
Where? The lone Gatherer's Garden in the balcony of the Welcome Lobby, waiting there just for you.
Upgrade? Yes (++)
This lets you set enemies on fire. One or two blasts drops an aggressor. If an enemy runs into another, that other will catch fire, too. Burning enemies could run for the nearest pool of water; get Electro Bolt ready to finish them off. You can also set pools of gasoline on fire to burn multiple aggressors, or set off barrels or cannisters of flammables next to enemies. And with one blast you can melt mounds of ice, no matter how big, making frozen doors and consumables accessible.
Watch yourself when applying this: Aggressors can still attack you, and if they are the melée-loving type they can set you on fire.
Where? In the Medical Pavilion, in the office on the upper floor of the Eternal Flame crematorium. Test it on the mob that Ryan summons after you take it.
Upgrade? No
This is a fancy word for 'mind over matter': You can pick up objects with your mind. You can bring them from afar and drop them down in front of you by pressing the V key. It is useful for getting goodies from off of high shelves or crevices; and it consumes no Eve.
Telekinesis also lets you pick up objects and throw them at your enemies. This does consume Eve, but not as much as Electo Bolt. You use Telekinesis to grab the bombs of Nitro Splicers, Rosie-type Big Daddies and Grenade turrets, to throw the bombs back at them, at other enemies, at security devices or at obstructions. With Telekinesis you can also throw all sorts of junk at your enemies, from furniture to gas cannisters to their own masks: A useful feature when you are low on ammo. You can even toss dead splicers (or test to see if they are just faking it).
Note: In the Fort Frolic quarter, you cannot pick up Cohen's disciples with Telekinesis. If you try, your avatar will go What?
Where? In the Medical Pavilion, in front of a Gatherer's Garden in the tennis practice room in Dandy Dental. Use the tennis ball shooter to test it out.
Upgrade? No
There is another way. Use this! Free them from their torment.
So says Dr. Tenenbaum as she tosses you this plasmid, which gives you the power to kill the sea slug inside a Little Sister, turning them back to a normal girl. The plasmid gives you the power to choose between harvesting and rescuing the Little Sisters.
Where? In the Medical Pavilion, in the lounge just off the hallway to Surgery. Dr. Tenenbaum tosses you the plasmid from a balcony. Test it on the Little Sister in front of you by choosing to rescue her.
Note: If you cannot obtain these plasmids when they first appear, you can get them at Gatherer's Gardens in subsequent levels. The only exception is Hypnotize Big Daddy.
Upgrade? Yes (+)
This lets you plant a stationary tornado at a given spot as a trap. Any aggressor stepping on the trap (which they can't see) is thrown far into the air, to meet with death or severe injury when they hit the ground. The little tornadoes do not work on Big Daddies. And you can't plant them on walls or on ceilings or on most areas of wather. And you can plant no more than five traps.
Where? Purchasable at the Gatherers Garden near the entrances to the Waterfall Grotto in Arcadia.
Upgrade? No
Hit one of a group of enemies with this ripe tomato, and the aggressor attacks anyone other than you — or, if there is nobody else around, you! The tomato locks on to its target, and on splash makes the target glow red as it screams its rage.
Enrage is useful when you want to thin out groups of aggressors without expending ammo, or when you want to weaken a Big Daddy without attacking it just yet. Oh, yeah, it works on Big Daddies, too.
Where? Purchasable at the Gatherer's Garden in the Medical Pavilion lounge. The tape describing the testing of Enrage (ending with the impaling of the nurse with a surgical saw) is in the back of the Kure-All clinic.
Note: Originally, Enrage was green, was called Splicer Irritant, and was meant to make other aggressors attack its target.
Upgrade? Yes (+)
Hit a Big Daddy with this fried green tomato to make it your bodyguard for at least a minute and a half. It will think you are a Little Sister, and so will attack anyone who attacks you (or whom you attack). This works best in areas with multiple aggressors. Use this with caution: It consumes a whole hypo of Eve; and it wears off immediately if you shoot your bodyguard by accident. You might want to be elsewhere when it wears off, lest the big guy smack you for playing mind games with it.
Where? Both levels of this plasmid are available from Dr. Tenenbaum only if you rescue Little Sisters.
Upgrade? Yes (++)
This is one ugly plasmid: Bees come right out of your hands and swarm over one or more enemies for several minutes, stinging them to distraction or even to death. An aggressor fending off the bees will be unaware of you, giving you a chance to whack or shoot them. Do not use if a Big Daddy is in the area, as he may walk into the bee field, and then you will have to duke it out with him, too.
Where? Purchasable at the Gatherer's Garden in the Silverwing Apiary at the Farmer's Market.
Note: I liked the prose of the Kriegsaffe No. 9
description of this plasmid from the Bioshock Wiki better than the new, improved one. I will quote the fun parts:
Plus, enemies are easily stunned by the horrible, horrible bees, unlike Incinerate, so you can give 'em a smack or a shot while they're busy reeling in bee-horror.
If a Big Daddy is in the area, don't even think about laying down a bee-field; because it lasts several seconds after you level your attack, there's a chance a wandering Big Daddy will amble into it, add you to his hit-list, and introduce you to a new age of pain. Single-target plasmids can pinpoint victims, making them more useful for super-powered-golemoid-and-indestructible-mutagen-sucking-waif-strewn battlefields.
Upgrade? No
Toss this bright blue beeper on an enemy which stands in front of a security device, and the device will interpret your enemy as theirs. Turrets will fire on the enemy immediately; cameras will summon bots to shoot out the enemy.
Where? Found spilt out of a Gatherer's Garden on the ledge of the Wharfmaster's Office, overlooking the Upper Wharf, at Port Neptune.
Upgrade? Yes (+)
This appears in the 1.1 patch: It generates a blast of wind that sends your enemies flying away from you. This is useful for knocking spiders off of ceilings. It does not work on Big Daddies.
Where? Purchasable at the Gatherers Garden in front of Fontaine Fisheries at Port Neptune, for a single unit of Adam, after you install the 1.1 patch.
Upgrade? No
Also called the Decoy plasmid. This projects a phantom self that, for a minute, deceives your enemies into attacking it, giving you time to escape or to prepare an offense. It does not work if your enemy is already aware of you.
Where? Purchasable at the Gatherers Garden in front of Fontaine Fisheries at Port Neptune.
Upgrade? Yes (++)
This lets you freeze your enemy into a solid block of ice. You can then shatter your foe into a thousand shards. Unfortunately, if you shatter an aggressor, you shatter their loot as well. This is also useful in freezing machines for hacking, as it slows down the fluid in the hacking puzzle, and is cheaper on Eve than Electro-Bolt.
Where? Purchasable at the Gatherers Garden in front of Fontaine Fisheries at Port Neptune.
Upgrade? n/a
This lets you fire a beam of energy that sucks the life out of your enemy and into you.
Upgrade? n/a
One of the demos demonstrates this plasmid, which lets you anchor a place to which you can teleport out of danger. It also shows it used by certain aggressors called Houdini splicers. The final form of the game had advertisements for the Teleport plasmid, and the Houdini splicers (starting in Arcadia); but a player-usable Teleport plasmid never made it due to scripting issues.