The Ultimate Power - Your Special Ability Units
The most powerful units available to you are those who are otherwise defenseless and easily destroyed: the special ability users. You must attend to the enemy's energy-driven special ability users more than any of his other forces, for it is they who are capable of harming a great many of your own troops in a single attack. Units with special abilities tend not to be useful on their own, but in support of standard fighting troops, they can be most deadly indeed.
A huge, expensive group of Zerg Hydralisks or Mutalisks in full health will die within a single Protoss High Templar's Psionic Storm. A pack of fearsome Protoss Archons will be instantly stripped of 350 points of shielding under the Terran Science Vessel's EMP Shockwave. The Zerg Queen may kill a deadly Terran Siege Tank instantly with its Spawn Broodlings ability, causing twin voracious creatures to spring forth from the destruction and attack any other tanks nearby. Though special ability users are fairly expensive, using them successfully in combat leads to devastating losses for the enemy such that your purchase will have been more than worthwhile.
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The High Templar's deadly Psionic Storm devastates a Zerg strike force |
Keep in mind that special ability users tend not to be effective until you research several of their powers from the appropriate structure. Further, they are time-consuming to produce and only begin with limited energy reserves, so you must defend them for a while until they are ready to use their powers.
The limitation of such units' power lies solely in the fact that you must micromanage them very closely. Take care to keep them out of harm's reach while being attentive of their energy level to make certain they may use their abilities when you need them most. Triggering their abilities properly in the heat of battle is a matter requiring precision, dexterity, and timing, and one that you must practice to improve. You must strive to learn the various hotkeys that designate your units' special abilities so that you may initiate them quickly during a conflict. Typically, you must use your mouse to select a High Templar, select the small Psionic Storm icon from the menu bar, and then choose a target, thus losing valuable time by covering a large area with your mouse. Fortunately, you can expedite this process by selecting the High Templar, pressing T which is the hotkey for Psionic Storm, and then designating the target. In this case, you needn't move your mouse over nearly as great an area were you not to use hotkeys.
Special ability units are targets of opportunity. If you see them among the enemy regiments, try and kill them first before they use their powers against you. Likewise, you must strive to master the powers of the special ability units at your disposal. Even if you face seemingly hopeless enemy numbers, these units may typically lead to your victory.
Next: Knowing How Best to Attack 
