Ghost

Ghosts are covert operatives in the StarCraft universe. They are known for their psionic powers and ability to become invisible.

The Terran Confederacy used to take children showing signs of psionic power and put some or all into the Ghost program. It is unknown what happened to children who were either not selected for this program or who didn't graduate.

The Terran Dominion has adopted this program, but perhaps choose their subjects differently. The Kel-Morian Combine also uses Ghosts, but it is unknown if the Umojan Protectorate does as well.

The United Earth Directorate has used Ghosts, even though its predecessor the United Powers League tried to wipe out mutants, including psychics.

The UED seems to have used psychic scientists who had not received Ghost training in their efforts to control the Zerg.

Ghosts are always psychic Terrans, and they use this ability to enhance their strength, speed and endurance. They are generally trained as commandos and assassins, appearing and striking suddenly and silently. In a particularly imfamous action, they used these abilities to execute Angus Mengsk, the father of Arcturus Mengsk, in order to shut down the rebellion of Korhal IV. His head was never found.

Ghosts are given some training in psionics, but not much. Their abilities are generally limited to personal augmentation (as detailed above) and mind-reading.

Ghost Training
The Terran Confederacy decided to limit Ghosts through at least four methods - a psi-dampener, also known as a neuro-adjuster (rumored to also suppress or reshape a Ghost's memory) which weakens their powers, neural processing treatments, aggression inhibitors (which prevent a Ghost from attacking his/her superior officers) and Ghost conditioning, a powerful form of hypnosis which restricts the use of their psionic abilities. This conditioning was so powerful that after Sarah Kerrigan was infested, she did not immediately lose this psychic hindrance.

The Terran Confederacy was rumored to have used Ghosts in a program to attract and even control Zerg.

Nova Squadron has recently become part of the Terran Dominion and have been training a Ghost known only as "Nova". In addition to the above abilities, she also seems to have the ability to see through walls and accelerate at four times normal human speed.

Game Unit
Ghosts are issued with a Hostile Environment Suit with a cloaking device powered by a personal Moebius fusion reactor and psionic powers (which stimulate receptors in the Ghost's suit). A Ghost can attack while invisible. While it is difficult to detect an invisible (cloaked) Ghost, it is possible.

Ghosts are also issued a C10 25 mm canister rifle. In addition to powerful, long-ranged anti-personnel rounds, it can fire a number of specialized grenades and missiles, such as the lockdown missile. This special missile can shut down machinery for a short period of time, but requires energy from the Moebius reactor to do so. The lockdown missile may be an electromagnetic pulse weapon.

In addition, Ghosts are frequently augmented with cybernetic surgery, especially their eyes. These cybereyes enable them to see objects much further than a regular human could.

Ghosts are equipped with a target painting laser device. By using it on a site for 10-15 seconds (real time) a ghost can provide targeting information to a friendly nuclear silo, enabling it to fire a tactical nuclear warhead. The Ghost is often within the blast radius and dies unless he or she has received the above optical surgery to increase vision range. In addition, the Ghost is completely vulnerable while using the targeting laser, and can easily be killed, which will result in an abortion of the nuclear launch. All forces in the region will detect the launch of the nuke (receiving the message "Nuclear Launch Detected" immediately as the Ghost uses the laser) and if they can see the target site, the target painting laser (a flashing red dot) is also visible. These two events serve to alert the enemy as to Ghost's presence and general whereabouts. Cloaking helps provide a degree of protection for the ghost, but is no guarantee when put against the aforementioned obstacles, as players will frequently bring whatever detection resources available to bear on the telltale red dot and therefore the nearby Ghost.

In StarCraft: Ghost, Ghosts will be a little different. Ghosts will wield an assault rifle/grenade-launcher combination as their standard weapon. It is less powerful than the C-14 "Impaler" Gauss rifle. This weapon is different from the original C-10 canister rifle.

In addition, Ghosts can use the BOSON FN92 sniper rifle (which is, again, different from their long-ranged canister rifle from StarCraft).

Ghosts in StarCraft: Ghost
In addition to using new technologies, Ghosts can be augmented using terrazine gas, part of General Horace Warfield's Project Shadow Blade. While the specifics of exposure to the gas are unknown, it is known to create a genetic mutation in psychics, such as Ghosts.

These Ghosts are transformed into Spectres - shadowy superhuman beings bent on executing the will of their true master.

Famous Ghosts

 * Sarah Kerrigan
 * Nova (of Nova Squadron)
 * Samir Duran
 * Alexei Stukov

Stukov was represented in-game by a Ghost. It's possible that he was a Ghost, was psychic but had not received (extensive) Ghost training, or that was simply used as a placeholder unit. The events of Ressurection IV suggest that he really was psychic.