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In appearance, Infectors look like a headless bat made from dead human material. The strange winged Infector acts as a vector for the disease, though it's not clear if it's the only one. Only attacking or defending itself when it cannot find any hosts to infect, its wings are formed by a flap of skin between the host's distorted arms and legs, with the head utterly unrecognizable, reduced to a strange proboscis. This weapon is the delivery mechanism used to infect potential hosts, which is done by enveloping the host in its wings and stabbing the proboscis into the corpse's skull to inject a yellow fluid stored in the creature's bladder. In any room with the remains of crew members, these are the beasts that should be taken down quickly before you get overrun with newly created Necromorphs.

They seem to have a preference for corpses which have existing head wounds, possibly because this spares them having to crack the skull themselves; the Infector in the Morgue goes straight for the captain, with his eye-to-brain needle puncture, over any of the other corpses, and Mercer is seen to have "prepared" corpses for them by boring a hole in the centre of their foreheads.

Infectors in the original game produce Enhanced Slashers, making it appear a mystery as to how the other forms of Necromorph are created. It is later revealed, first in Dead Space: Downfall and then in Dead Space: Extraction that they can also produce ordinary Slashers, and, by implication, the various other breeds of Necromorph as well. It is unknown why they are only shown producing such a limited variety of Necromorphs; two possible explanations are complexity of programming and, in the first game, an effort to install a sense of urgency. By having an Infector produce a particularly onerous opponent, extra urgency is thus directed towards the elimination of any Infectors that are on-screen.

[edit] Strategy

• The creature is unique in that it has only one limb to dismember: the infection proboscis. Wait until it latches onto a corpse before using stasis and shooting the proboscis as it emerges. The other tactic is to simply shoot it to death.
• The Flamethrower is highly effective against them.
• If you encounter an Infector as it is in the middle of infecting a corpse, immediately target the corpse and shoot it with whatever you have. The Infector will abort its efforts if you damage the corpse enough Even if you fail, any damage you inflicted to the corpse will be carried on to the newly spawned creature, making for an easier kill.
• Stomping on corpses enough times can sever the limbs, making the corpse too damaged to infect. An Infector would still consider a legless corpse good enough to infect, so be thorough.
• Try cutting only the corpse's arms off; use the Plasma cutter so you don't accidentally stomp the head off. The Infector would still try to create a Dark Slasher out of the damaged corpse, but the newly born Slasher would die instantly and possibly leave loot behind! Note that an Infector would not go for an armless and headless corpse, so keep the head!
• The creature can initiate a grapple sequence with Isaac. If Isaac escapes, he automatically kills the creature (by pulling the Infector off and tearing off its proboscis).
• If the Infector has latched onto a body, the Line Gun can be put to good use; not only will the Line Gun damage the Infector, it can preemptively dismember the resulting Necromorph or even damage the corpse badly enough that the Infector aborts its efforts.
• If you're close enough, the Force Gun can also damage the Infector as well as also being completely guaranteed to blow the body to bits and pieces.

[edit] Trivia

• In the movie Dead Space: Downfall, the fall of the Ishimura was due to an Infector slipping onto a shuttle when a miner boards, with the corpse of his wife, who manages to crash it into the Ishimura docks past the closing bay doors. Unlike Infectors portrayed in the game that always crawl over the floor (with only one instance of an Infector seen flying, and another seen sitting on the inside of a window), the movie's Infectors rely on flying as their primary means of transportation. Infectors in the movie also directly transfer the infectious vector into the corpse through their proboscis, while Infectors in the game use an appendage to draw the corpses to them before infecting the victim, transforming it into an enhanced Slasher.
• The creation of an Infector is detailed in a backstory log.
• Several logs in Dead Space allude to those infected as aspirating a yellowish bile from their mouths as one of the first signs of transformation into an Infector.
• The yellowish-bile comes out of an Infector like blood from other Necromorphs, though blood may be present as well.
• A medical officer in the Imaging Diagnostics lab chapter vomits yellowish bile, the first sign of becoming an Infector, during Chapter 2.
• The yellowish bile is likely the bacterial basis of Necromorph existence.

[edit] Death Scene

When Isaac fails to kill an Infector that has latched onto him, the creature impales him through the forehead with its proboscis. It then uses it to stab into Isaac's neck three times, with the third stab completely decapitating him.

Necromorphs
Forms		Brutes • Dividers • Drag Tentacles • Exploders • Flyers • Guardians • Infectors • Leapers • Lurkers • Pregnants • Slashers • Swarmers • Twitchers • Wheezers
Bosses		The Leviathan • The Hunter • The Slug • The Hive Mind
Deleted Material		Grabber • Graverobber