The Protoss

The Protoss are an advanced alien race who use their advanced understanding of psionics to augment their abilities. They warp in thier buildings via probes and do not require the worker to remain with the building while it warps in (as opposed to Terran SCV's which build buildings and Zerg drones which morph themselves into buildings). All Protoss units and buildings have energy shields in addition to regular health which absorb damage and then recharge.

Protoss units are expensive, slow to build, and very powerful. The base unit of their army, the Zealot, is a melee fighter with a psionic blade on each hand. It can easily kill any single base unit of the other races. Depending on the skill of the players involved, a zealot can kill two marines (the basic Terran ranged unit) and four zerglings (the basic Zerg melee unit).

Two of the most interesting Protoss units are the two templar: High and Dark. In Starcraft lore these two templar were at odds, and each others throats, for many many years. After the Brood War they reconciled their differences and agreed to fight on the same side. High templar are spell casters without a basic attack. They arrive on the battlefield capable of casting Psi Storm, which the player activates. It zaps everything in a small area for a significant amount of damage. Dark templar are permanently cloaked units that attack with psionic blades, simillar to zealots. They deal massive melee damage and can be very nasty to deal without some sort of detection. But what makes these units so intriguing to me is their peripheral ability: you may combine any two templar to form an archon. Archons are beings of pure energy and manifestations of rage incarnate. They attack with powerful psionic blasts and have formidable shields capable of taking an amazing amount of damage. They have very little health, however, and once the shield is gone they are easily dispatched.