Starcraft Strategies Breakdown of Each Match-up

After playing Starcraft: Broodwar for nearly eight years, as well as playing intensive melee for two years, there are some patterns in each type of match up. Before getting into those, let's look at the general advantages of each race.

Terran - highly efficient but not powerful nor weak. The "middle" of the three races, if such a thing is possible.
Protoss - extremely powerful but expensive. Quality over quantity in this case.
Zerg - extremely weak unit-wise but can be produced at a rate faster than the other two races.

This article will cover three of the six combinations: Terran vs Terran, Terran vs Zerg, Terran vs Protoss

Terran vs Terran: Most commonly, the goal is to tech into Factories and Armories, producing Tanks and Goliaths which can take on all other units up to that tech tree while still being efficient to produce. Sometimes, a marine rush is employed to slow down the enemy from teching by destroying the SCVs, thereby ruining their economy. The Tanks and Goliaths will generally produce a draw if both players reach this tech while maintaining a decent economy. In such a case, the players will try to go expand and eventually produce either Battlecruisers or, rarely, Nuclear Missiles. Because the range of Yamato Cannon is greater than the range of any anti-air unit Terran has, it is the best choice to break through with these slowly, allowing the energy of the Battlecruiser to recharge as needed. A well-placed nuclear strike is very difficult to place; in the event that one falls, then the defenses of the enemy is instantly destroyed, allowing your own forces to charge in easily.

Units rarely used by both: Ghosts, Firebats, Vultures, Wraiths, Valkyries

Terran vs Zerg:
Terran - Because Zerg can overrun Terran relatively easily, Terran must produce highly efficient units. Marines (and a few Firebats later) and Medics is a staple in these match-ups because they can handle all but the most powerful Zerg units while losing very little (this is so efficient that it is possible for the Terran to hold on indefinitely if Zerg does not go higher in the tech tree). Depending on what the Zerg does after this, the next unit to get is the Siege Tank. This unit has the highest range in the game as well as having a splash damage, excellent for taking on the masses of Zerg that are sure to swarm the Terran forces later. This unit is highly effectively against Lurkers and Ultralisks, employed only in the middle to end game. Science Vessels turn into a must later on as Irridiate produces a never ending attack against the Zerg and Defense Matrix allows even a simple marine to be as powerful as ten Hydralisks or stall an Ultralisk. To end games, it is not uncommon for Terran to starve the Zerg by waiting and stalling. Other times, if resources allow, Battlecruisers will be used to break through the deadily Defilers and Hydralisks.

Zerg - Knowing that starvation is always a problem, the Zerg must expand early. Many times, players will get another Hatchery before the Spawning Pool. Although this slows down going up the tech tree, the long term benefits are unrivaled. Since the Zerg can only produce the same number of larvae they have, having two Hatcheries is essentially doubling the number of units being able to be produced at any one time. Massing Zerglings against Terran will generally not work because of how efficient the Marine and Medic combo is.Thus, the Zerg must try to harass SCVs and slow down the Terran economy while climbing the tech tree at a faster rate. The best way to do this is Mutalisks because of their speed and cost.

Lurkers is also a viable alternative but relatively much more difficult to use because they are better at a straight out attack. If the game continues to the point that Terran has produced Tanks and masses of Marines, the Zerg must get Ultralisks with upgraded Zerglings. This is the single most deadily ground combo in the game as Ultralisks soak damage while the Zerglings devour all ground unit. This works especially well with Defiler's Dark Swarm because Terran has no melee unit. In the unlikely case that Battlecruisers are employed, the best strategy is not Scourge (although they work wonders against Science Vessels) but Defilers and Hydralisks. The range of Hydralisks is almost equal to the Battlecruiser after upgraded; the real advantage is the two abilities of Defiler: Dark Swarm, nullifying the attacks of Battlecruisers and Plague, which will eventually bring down all Battlecruisers infected to 1 or 2 hitpoints after a little of time.

Units rarely used:
Terran - Golaiths, Vultures, Valkyries, Wraiths, Battlecruisers, Ghosts
Zerg - Devourers, Guardians (used only when necessary)

Terran vs Protoss:
Terran - Straight out, the Terran must advance to Factories as no infantry can hold their own against Zealots without back up. Vultures and Tanks are the strongest and most cost effective in handling the powerful strong Protoss units. The most common strategy is the Tank push, a combination of Siege Tanks, Vultures (fully upgraded) and SCVs to repair and build Turrets. The "push" is where the Tanks slowly advance with Spidermines placed ahead of the battle to ensure all ground units are weak if they attack directly while the Turrets act as both anti-air and detector units. Due to the long range of Tanks, they can easily blast unit Protoss bases while being in safety. At this point, Protoss will try to get Carriers, the only unit capable of stopping such a push. In this case, there are two options: stay with the current tech tree and produce Goliaths, an inferior anti-air unit when compared to the Wraith but requires less resources, or move to the Wraith, which can cloak and destroy Carriers quickly. Goliaths are used more commonly but I have found both to work if micro is used. Because Golaiths fall to Dragoons too quickly, Tanks most still be produced to counter ground units.

Protoss - Teching to Dragoons and Observers is the most important step because of the threat of Spidermines, invisible exploding mines. Upgrading the range of Dragoons is usually the first upgrade because it allows easier and more powerful micro. There are a number of possible things to try; the most common is to simply produce more Dragoons and Zealots to gain ground and expand to increase resource input. These two units can break through the deadily Tank push but will cost significantly more than the Tank combo. Other possible strategies at this point include teching to Dark Templars, an invisible unit that can kill Peons quickly because of their high damage. This works extremely well if Terran have not produced any detector units yet which, oddly enough, is quite common because of the awkward placement of detector units in the tech tree of Terran.

Another common strategy is to try to create a Reaver drop aimed to take out the SCVs. Note that both is to simply try to mess up Terran's economy. High Templars are used often because of their low hit points but can be used as a support unit with Hallucination and Psi Storm. If the Tank push is successful (which can be seen well before it actually succeeds, giving plenty of time for the Player to change tech trees), Protoss must try to change to Carriers, or less often, Corsairs with Disruption Web. In either case, Stargates and Fleet Beacons are required, both of which cost quite a bit. Corsairs is the cheaper alternative but is very difficult to use because of the amount of micro involved and requires a decent ground force. Carriers, the more common alternative, can easily punch through the Terran blockade but micro must be employed to ensure the actual Carriers are not hurt.

Units rarely used:
Terran - Firebats, Marines (a few per game), Medics, Ghosts, Battlecruisers, Valkyries
Protoss - Scouts, Arbiters (in very specific cases), Corsairs