Sentry

The sentry is a protoss support unit introduced in StarCraft II available early in the game. It was previously known as the disruptor, and nullifier before that.

Overview
The sentry was seemingly designed by the Dark Templar.

Game Unit
The sentry had a beam which does continuous damage to one target.

Sentries are very strong against Marines and Marauders, fairly strong versus Mutalisks, Hydralisks, and Stalkers, and weak against Hellions, Zealots, Banelings, and Zerglings. They tend to be very complimentary to Zealots.

Abilities

 * For the terran-devised force field, see force field (terran).

Strategies
Sentries can use Force Field to isolate enemy workers, preventing them from escaping their onslaught. Sentry's deal bonus damage against biological units, making this a particularly effective tactic against drones. Force Field also proves to be very effective for splitting forces or preventing them from escaping at choke points in early stages of the game.

Development
The sentry was previously known as the stasis orb. The Force Field and Anti-Gravity abilities were used by the high templar in earlier builds of StarCraft II. Anti-Gravity was later moved to the Phoenix.

In earlier builds, Anti-Gravity could affect destructible doodads, but this was a bug.

Earlier builds featured an ability called Null Void.


 * Null Void
 * Ability Cost: 50
 * Prevents any unit caught in the target area from using abilities that cost energy. It does not affect abilities such as a stalker's Blink, a carrier's Build Interceptor, a Phoenix's Overload or an SCV's Repair. Immediatly upon exiting a field a unit can use its powers like normal
 * Nullify acts as a detector, decloaking units such as ghosts and dark templar and revealing burrowed units. The ability to detect cloaked and burrowed units is currently being subjected to balance testing.
 * The effect lasts 15 seconds.

As of February 2009 the nullifier lost the Molecular Disruption ability.

Trivia
As a disruptor, the sentry resembled a trilobite.