Starcraft 2 Protoss Support Units

Starcraft 2 Protoss Units and Structures --> Protoss Support Units (you are here)

In Starcraft 2, support units are units that would be ineffective alone but lend support to more powerful units. These units have synergistic abilities that make offensive Protoss units more powerful.

Units covered in this section: High Templar, Mothership, Observer, Sentry, and the Warp Prism.

High Templar

Cost: 50 minerals, 150 vespene gas, and 2 supplies.
Requires: Templar Archives

The High Templar is a specialty unit with 1 main ability: Psionic Storm.

Psionic Storm is an ability which damages all units within the target area over time. It is very damaging but only effects a small area.

Psionic Storm deals an actual damage amount; it does not take away a percentage of the unit's health. It is most effective versus "light" units as a result - a Psionic Storm barely scratches a Battlecruiser and absolutely decimates Marines.

Enemies can escape the damage by moving out of the stormed area, so it is most effective when enemies are boxed in by large numbers (common versus Terran who are limited by Siege Tanks) or with the Sentry's Force Field ability.

This ability is very powerful and can easily turn the tide of a battle. The major downsides are that it is difficult, time-consuming, and expensive to use.

Templar are a high-tech unit and Psionic Storm has to be researched, making this a time-consuming endeavor.

Additionally, it costs a lot of vespene gas to research and Templar themselves cost a lot of gas, making this unit and ability expensive to use. However, in late game situations, it is definitely worth having!

I have also seen many Diamond-ranked Protoss players successfully teching quickly to High Templar in order to stop Terran Marine and Marauder armies. These players mass Zealots to save vespene to spend on High Templar.

The High Templar also has an ability, Feedback, which can deal damage to units with energy. This can be used to quickly damage light units who have more energy than health, such as other High Templar, Zerg Infestors, or Ghosts. Having a quick finger to use Feedback on Ghosts is very important in Protoss vs. Terran match-ups.

Mothership

Requires: Fleet Beacon, Nexus, No Mothership (you can only have one)
Cost: 400 minerals, 400 vespene, 8 supplies

At a cost of 8 supplies, the Protoss Mothership is the biggest and most expensive unit in game. You can build one of these at your Nexus if you build a Fleet Beacon.

This unit is a lot like the Arbiter of the original Starcraft. The primary difference is that the Mothership is a lot stronger and its abilities are a little different.

Mass Recall can be used to teleport your units to wherever the Mothership is. This can be a way to quickly bring units to battle or summon units into the enemy's base, skipping his defensive structures.

The other major ability, Vortex Field, can disables all units that enter it for 20 seconds. Units in this field are not targetable. This can be devastating late game if the enemy has a lot of forces. This ability can easily turn the tide of battle by hiding half of the enemy's units while you pick off the rest of them. 

Observer

Cost: 50 minerals, 100 vespene gas, 1 supply
Requires: Robotics Facility

The observer is the Protoss' stealth detecting unit. It is a flying unit and is permanently cloaked. It has no use besides looking for cloaked units and scouting out the enemy. It cannot attack and has no other special ability.

With that said, it is the best detector among the races. Since it is permanently cloaked and is hard to see on screen, it is actually pretty tough to find and kill these units in the heat of battle. Their survival is practically guaranteed.

The major downside to this unit is that it requires a robotics facility and a fairly high vespene gas cost. It can be upgraded to move faster at the Robotics Bay.

Sentry

Cost: 50 minerals, 100 vespene gas, 2 supplies
Requires: Cybernetics Core

The Sentry is a deceptively powerful Protoss support ground unit. The Sentry has a moderately powerful ranged attack that can hit both air and ground units.

The real power of the Sentry is its ability to create force fields. The Force Field ability can block enemy units from coming into the base (use it on the ramp), giving stalkers the opportunity to pick the enemy off from a safe position.

This ability can also be used to prevent fleeing units. This ability makes the Sentry / Zealot combo potent as Force Field can trap fleeing enemy units so that Zealots can catch them.

Additionally, the Guardian Shield ability provides a small defensive boost to ranged attacks to all units in the area. This makes the Sentry (in conjunction with other units) particularly effective versus light ranged units such as Marines and Hydralisks.

You can research a "Hallucination" ability with these units, which has some uses for scouting and deception as well. 

For a full article on the Sentry, see the Starcraft 2 Sentry article.

Warp Prism

Cost: 200 minerals, 2 supplies
Requires: Robotics Facility

The Warp Prism unit allows the Protoss player to carry ground units and then unload them at another location. All races have a ship like this.

The Warp Prism is unique in that it can also function as a portable pylon. In conjunction with Warp Gates, this is a powerful way to summon units into the enemy's base or to front lines of battle.