Terran gameplay (StarCraft)

Gameplay attributes

 * Average cost units and buildings
 * Generally fragile units with high damage, ranged attacks
 * "Lift Off" allows key buildings to relocate
 * Moderately efficient building method
 * Forces need preparation prior to combat to be most effective; s with StimPacks, s in siege mode, missile turret and bunker construction, spider mine laying, etc..
 * HP recovery is only through unit abilities; SCVs repair buildings and mechanical units, medics (StarCraft: Brood War only) heal biological units and SCVs. Buildings lose 1 HP per second once their HP bar turns red and are destroyed unless repaired.
 * Increased micromanagement requirement.

EMP Shockwave
Science vessel ability. Completely drains the energy and shield points of all units caught in the area of effect. Particularly effective against protoss units and buildings, especially archons. It also destroys Hallucinations.

Nuclear Strike
ability, armed at nuclear silo. The missile deals 500 damage, or damage equivalent to 2/3rds of a unit's maximum HP, to objects at the point of impact. Units within the area of effect are dealt reduced splash damage. The ghost's Nuclear Strike ability paints the point of impact from a distance with a red dot visible to all players. If the ghost carrier out any other actions before the missile arrives the strike is terminated and the missile lost. A ghost without the Ocular Implant upgrade must paint the target within the blast radius; the ghost must flee immediately when the missile arrives or be killed.

Yamato Cannon
Battlecruiser ability. Fires a bolt dealing 260 damage at range 10, one of the longest ranges in the game, for 150 energy. The range is slightly greater than the battlecruiser's sight range, so a spotter is ideal. If the cannon is charging and the intended target is destroyed, the energy is still expended but the cannon does not fire.

Heal
Medic ability. Allows s to make more extensive use of StimPacks. See "medics and marines".

Techs
Terran players usually follow one of two main general tech trees: 1) Biological (infantry) and 2) Mechanical (metal). It is not good to mix and match (unless engaged in a long match) because many buildings (such as academy/engineering bay and armory) upgrades for only one of the two tech trees.

1) Biological is often used against zerg opponents because of just how effective marine/medic is against almost all zerg units (with the exception of lurkers). It is not as effective against protoss or terran units because these races have more larger-damage units, with splash.

Against zerg opponents, a typical build order would be a couple of barracks and supply depots (can also implement building block - see Strategies), refinery, academy, more barracks, ComSat, factory, engineering bays, starport, science facility, and then expand to more buildings as you see fit. Generally, terrans can just pump out Marine+Medic, some tanks for siege support, ComSat for detection, and science vessels for detection and irradiate.

2) Mechanical is almost always used against protoss and other terrans because infantry is often ineffective. The mechanic units include tanks, vultures, goliaths, and maybe Wraiths and battlecruisers.

Against protoss and terran opponents, a typical build order would be a supply depot + barracks building block (see Strategies), factory (2), starport. From then on, the terran will have to choose which specific strategy to implement, depending on various circumstances.

Strategies
Here is a list of some simple and common terran strategies:

Wall-in — This strategy is also called "turtling." In the early game, ground entrance to the base may be through a choke point easily blocked by a supply depot and barracks. The barracks, with Lift-off, may be used as a gate. Attackers are forced to destroy the buildings before entering the base. Meanwhile the defender may repair the buildings with SCVs and respond with ranged attacks from marines, and later siege tanks. In the meantime the terrans may tech up for a mech build. Walling may also be applied to expansions, to buy time for reinforcements to arrive, or, occasionally, used offensively.

Dropping — One of the most notorious attacks terrans are known for. After teching to starport and getting dropships, terrans can drop units by loading them into dropships and dropping them near weaknesses in the enemy base, causing large amounts of damage. For example, terrans often drop siege tanks onto cliffs overlooking the enemy base and immediately siege them, attacking their buildings and units. Because the tanks are on high ground, the enemy cannot easily fend off the attack. Drops can also be tactically used to destroy the enemy resource gatherers (using fast-attacking concussive/normal damage type units such as vultures and marines) and delay their economy for quite a while. And finally, drops can also be used as a large-scale attack force. Sending a group of 6-8 dropships and a science vessel or two, terrans can unload a whole army of tanks, goliaths, and marines+medics inside an unguarded point in the enemy base.

Wraiths — Wraiths are often used against enemy terrans, due to their lack of ready detectors. With their Cloaking ability, Wraiths can attack targets unguarded by stationary turrets or science vessels. Even with a ComSat scanner, detection is only temporary; the Wraiths can retreat, and attack again. In addition, a Wraith rush can be somewhat effective against zerg players in hunting down overlords and slowing down their army. Wraiths are also very good for harassing.

Irradiate — Used primarily against zerg opponents, or expensive protoss units such as a high templar or dark templar. A variant strategy involves irradiating one's own mechanical unit (such as another Science Vessel), and moving it into melee range with enemy units, particularly workers, damaging and killing as many as possible before the Irradiate wears off.

Tank Push — This refers to the practice of "leapfrogging" siege tanks into enemy positions. Since the range of sieged tanks is so large, one can attack the enemy base and destroy its front-line defenses, then inch some tanks forward and continue destroying the defenses behind those.

Bunker Hopping — Refers to the similar practice of "leapfrogging" bunkers. One bunker staffed with marines is used to defend the SCV building another bunker which is then staffed to protect the building of another bunker, et cetera, to create defense in depth. Not nearly as effective as Tank pushing and is no longer a common strategy.

Good Bunker Defense- One common mistake that amateurs make is randomly placing their bunkers, goliaths and siege tanks, creating a divided defense system. The proper placement of defenses is to have bunkers in front that are being repaired by SCVs, followed by goliaths or missile turrets, and finally siege tanks at the rear. This strategy is most effective when it is used in the vital choke points of your base, reducing the effectiveness of swarm assaults by terran or zerg opponents but is extremely vulnerable to attacks by zerg using dark swarms.

Against the Zerg
It is important to remember one key philosophy in Terran vs Zerg (TvZ): Don't let the infestation spread. Terrans have the advantage in the early and especially in the mid game and they have to use it. Advanced hive tech allows the zerg to easily match terran late-game strength. If zerg are allowed to survive with a functioning economy into the late game, a terran base will be overwhelmed with hordes of upgraded units, and any defensive line, no matter how massive, will eventually be broken.

Early Game is classically a split between the popular fast expansion("fe") and a direct strike on the zerg main base. The decision is typically settled by the opening scout (most professionals will send an SCV to scout their opponent between 8/10 and 10/10 population). The scout will reveal if there is any opportunity to perform a marine rush on the zerg base. The rush requires immediate construction and research of academy technology, specifically medics and stim packs. Grouped correctly and with sufficient numbers, a small early-game force of marines and medics can often beat the first few defensive zerglings with minimal casualties.
 * Medics should be prevalent enough to allow for regular stim use without any concern for the medic's energy level, as this gives a terran player double the firepower from his marines.

Mid Game The balance can quickly shift against an unwary terran player when the zerg acquire lair tech. The best way to spot this is through frequent ComSat checks, though most competent players can be expected to pursue this line very quickly, as a force of zerglings and hydralisks can overwhelm defensive marines and medics for relatively low cost. Fortunately, sufficient zerg forces to defeat marines and medics require sizable quantities of gas, so if a terran can keep casualties to a minimum, the zerg player's economy will be re-purposed to create more units (an opposition a reasonably competent terran player could defeat) as opposed to advancing up the tech tree (a much harder foe to conquer).
 * If you spot a zerg player constructing a lair, you should construct an engineering bay at once if you have not already. Most zerg lair tech is best handled in part with missile turrets.
 * Mutalisks are very threatening because of their speed, the second fastest in the game. Zerg players typically attempt to bottle up terran opponents by threatening their main with fierce hit-and-run micro.
 * Terrans who see the spire go up should immediately turret their resource line, barracks, and base, as spread out static defenses minimalize ricochet damage and ensure total coverage of the base. You will have to support your turrets with M&amp;M's or the turrets will get overwhelmed, but turrets will drastically slow down mutalisk strikes and soak a lot of damage for their cost compared with 40hp marines. While Turrets will hold back mutalisks science vessels are the best way to end them. Irradiate(range 9) has a nasty habit of inflicting excessive damage on tightly grouped mutalisks, and loosely grouped mutalisks are usually not the best solution.
 * The potential, though unlikely, progression from mutalisks is Guardians, and Science Vessels will be a complete deterrent from this as a single irradiate practically now pays for each science vessel you build.

It should be noted that mutalisks tend to be ignored if a base harass is thwarted, as mutalisks have little value on the defensive. Because of this average players may pursue lurkers to keep up the contain if their mutalisks are stopped not having the Hive tech for more aggressive answers to Infantry. Please note that a Potent Zerg player will not have this problem, as Hive tech comes quickly when they know how badly it's needed.


 * Lurkers are one of the few Zerg units endowed with splash, and thus the only other effective counter to mass infantry at Lair tech. One of the bonuses of getting the Engineering bay up is Infantry Armor Level 1 which makes marines 3 hit kills to lurkers(and 5 hit kills to mutalisks, plus reductions on ricochet). The other bonus is being able to get cheap permanent detection on the map, which later helps ward off lurker drops.
 * If you believe that your opponent is going Lurkers your top priority should be producing science vessels, as the irradiates will quickly pay for construction, as will the map control from being able to save comsat scans.
 * Siege Tanks are an important sub set, as they will give you the range to attack the now exposed lurkers with ease, but they should not be overemphasized, as tanks are easy targets for zerglings, which are a gas free counter. Science vessels, on the other hand, will continue with irradiation effects while requiring gas intensive counters to be handled. In other words, there are better things to put gas into than tanks, specifically science vessels and dropships.
 * The goal of tanks is to attrition lurkers, not necessarily to obliterate them. If you can force them to move you can win the battle because of the myriad options a mid game terran player has against lurkers.
 * ~ M&amp;M's can micro very effectively against lurkers, and will frequently drain a great deal of gas from a zerg player who doesn't support his Lurkers with zerglings. You need to stim whenever you expect the lurkers to unburrow, particularly when you begin to siege your tanks in front of them. This way, if they try to get up and run, your marines will be faster.
 * ~ Dropships are just as vital as marines, and a well placed drop can encircle the lurkers, either cutting them off from reinforcements or more likely retreat. This is risky without knowledge of much of the map, however, as marines placed directly behind front lines can be just as easily encircled if your opponent sees what you're doing and keeps his lurkers in the ground. A better option is for you to find your opponent's tertiary or quaternary expansion for a drop. A good player will send a lurker or two to defend completed hatcheries, but if he's pushing your front he might forget, or simply prefer to use all of his available lurkers to occupy your marines in the hopes that you might forget how critical a successful drop can be at this phase in the game. No matter what, being able to drop will pull lurkers off his front and likely distract him long enough to force a speedy withdraw from battle, rather than the micro intensive slow one that will allow him to freely pursue Hive Tech.

Hopefully you will have noticed that every zerg tactic mentioned above is essentially a stall tactic, that is both because of the dominant position terrans have at this point in the game, and because of the untold horror which the Zerg can unleash against the Terran:

Hive Tech: marines are crucial to fight the zerg, as they cost no gas but there is little a zerg player can do to fight them that doesn't cost a great deal of gas. As great as it may seem, the zerg have some tricks left that will even the odds in every late game scenario where the terran player does not have a dominant position on the map.

We'll start with the least micro intensive tactic that everyone can use with maniacal joy; ultralisks. This unit is the antithesis of a Zerg unit; everything that a zerg unit is the ultralisk is not. It is not small, it does not have low hit points, it does not need to be massed, it does not burrow, it has a low attack strength, though it does have a bit of speed for a 400 hit point mastodon of bloody fury. The upgrades Brood War expansion has bestowed on ultralisks render these monsters a total affront to any god a terran has bowed before. I complain, but the terrans have the medic and Charon Boosters, and that's not too bad. So, your opponent is building ultralisks, what now?
 * Keep Building Marines. It sounds hopeless when your marines are only doing 3 damage a shot to 400 hit points, but they didn't cost you any gas, which makes them great filler. They also are important for killing whatever else the Zerg player builds to support the ultralisks. Typically this support is composed of zerglings, as they cost no gas, which are best handled by your marines. There's also the fact that Ultralisks have a fairly low damage rate, so most of the losses players see when Ultralisks are deployed don't come from the Ultras at all, which means they will never be the only thing you have to deal with.
 * Cast Defense Matrix(DM) on your front line marines. If you've got the fingers for it this works great, suddenly a 200 mineral 200 gas 400 hit point giant doesn't seem so menacing when you can make 290 hp foot soldiers for 50 minerals and 100 energy. This is a really good reason to have science vessels in your late game.
 * Irradiate the ultralisks before they start attacking your marines. Often you can encourage an ultralisk attack to happen prematurely by irradiating the intended ultralisks. They won't die, but losing 3/4 their hp is pretty close.  If your opponent does attack this will likely mean that his ultralisks will also deal irradiation damage to the zerglings in the control group, and those zerglings are after all your real targets.
 * Use tanks. The obvious approach is to use the massive explosive damage of tanks to quickly bring down ultralisks, but this is contingent on your tanks actually targeting the ultras and not the supporting lings and also to your tanks not dealing splash damage to your own troops. The worst part of this strategy is that should you be overcome you will have little hope of your tanks surviving point blank Ultra-ling. Some of these problems can be fixed by using unsieged tanks which don't deal splash damage to your units, but this play is only worth while if you have excess resources given the heavy reduction of ultra armor, and the low armor of tanks(less per mineral than a marine!). Always Defensive Matrix your Tanks before your marines.
 * Spider mines. The only time vultures should enter into a TvZ match up. 125 splash is a good way to cut through 400 hit points, shame that ultralisks set to Attack-Move can attack and kill a spider mine in one hit before it has a chance to detonate. Basically this means that spider mines are only useful if the ultralisks are already chasing something else, which takes out a lot of their punch. This strategy is usually seen as an act of desperation, and it is.

Defiler A competent zerg opponent will use both defilers and ultras for excessive amounts of annoyance and advantage. The ultralisk's role is obvious. What's important here is the defiler's role.

At 350 gas the defiler is by far the most important target to irradiate. Sadly Irradiate does not stop a defiler, it only determines a life span. Still, if you can keep your science vessels aggressive and your opponent's gas low defilers can remain a contained threat. However, to maintain this situation practically requires you to destroy your opponent outright, which is highly recommended. Your best bet is to destroy your opponent's expansions, cutting his ability to field an army which could benefit from such awesome tech:
 * Dark Swarm (100 energy, or 2 zerglings)("DS") Completely Blocks all direct fire from ranged units. This leaves a terran with Tank Splash and Irradiate, which is why you should run from or past dark swarm. Note that Splash damage does not effect burrowed units, which means that a few lurkers burrowed under a perpetual dark swarm can form a pretty effective seal on a base until you have the energy to irradiate all of them.
 * Consume (+50e, costs one unit) This is what really makes a defiler incredible. The fact that you can buy energy for a single defiler with crystal and never have to worry about recharge rates breaks the natural rules of casters. With this even an Irradiated defiler can cast 2 to 3 spells and mostly be limited by how fast it can scuttle within range of targets. For this reason above all else the defiler should be not be allowed to enter the field of battle if it can be at all helped.
 * You may also see Plague, particularly because it's a good way to spend 3 lings when a defiler has already been irradiated, so watch out for the lone mutalisk which will come around to do one hit kills on any sci vessels affected by plague.
 * The best way to handle defilers is to keep moving, either falling back of pushing forward. Always be ready to flank, and never hole up. To this end dropships and science vessels are the only real salvation you can hope for.

To make final what has been said
 * Pump Infantry.
 * Push your mid game offense.
 * Destroy your opponent's expansions at every chance you get.

Against the Protoss
Because terrans have the weakest early-game detection, a popular protoss strategy when dealing with terran players is to wall himself in with photon cannons while teching to Dark Templars. The Dark Templar Rush as its called is quite capable of causing severe damage to an early game terran assault, for Templar can one-hit kill Marines, and slice Missile Turrets to pieces easily.

There aren't many ways to prevent this. In a map like Lost Temple, the terran should attempt to block chokepoints with supply depots with a single Barracks being used as a "Gate" of sorts, lifting off to allow your own troops to move through, or landing to prevent enemies from advancing. Supported with two or so missile turrets, this will prove a decent defense unless the enemy decides to use a shuttle and just fly around these defenses. Additionally, hotkeying a Comsat Station can work in a pinch; the 1-s-click as its called can temporarily nullify the Templar cloaking ability. Spider mines also work for they home in on cloaked units, and as of more recent patches, a Dark Templar has 40 Shields and 80 HP, meaning that a spider mine will kill it in a single hit while weakening any nearby Dark Templar.

The same wall-in suggestions work when fighting a Zealot Rush, for between their speed and durability, zealots generally will just run past the terran's base defenses and go straight for the SCVs, crippling the economy enough to win the production war that is Starcraft. Walling in works well for hindering the movement of zealots, especially if bunkers comprise some of the walls.

Concussive-damage units are a lot more effective against protoss than normal, since Shields take full damage from every attack type. Firebats in particular easily beat their cost worth in zealots as the splash-damage combined with protoss bunching to attack units makes them very damaging. Keep a few medics around to allow more liberal use of Stimpacks; such a defense should help protect against the protoss until one techs to vultures.

Vultures are perhaps the best mid-game unit to use en-masse vs. protoss. A single vulture is cheaper than a Zealot and does more damage for the cost, and at range. 8 Vultures can take out a zealot in a single salvo, and with proper micro can defeat many times their cost in zealots. Versus heavier units like dragoons, they can run up, deploy a mass of spider mines, then retreat; this tactic can easily be supplemented in the late-game once Ghosts appear, for protoss have no counter to Lockdown. Lockdown several dragoons and Reavers, and ride the vultures up to drop spider mines adjacent to them. Such harassment works until siege tanks become available.

Against protoss, keeping siege tanks in Tank Mode is a viable strategy. The protoss units are generally durable enough to shrug off singular Siege Mode attacks that enough zealots rushing a tank emplacement will win out; between those and Corsairs, unless the tanks are being used for a specific purpose like shelling Photon Cannon emplacements or Reavers, they work best for hit-and-runs. They make good dragoon hunters for such is the attack animation that a Tank shot is instantaneous and a dragoon shot travels before hitting. Combined with a dropship, a terran can quickload a tank before it takes damage, then unload it. However, this trick requires experience to pull off.

When it comes to aerial battles, Wraiths are the main unit to use against other protoss air units for protoss have the weakest late-game detection. True they have observers but even observers are vulnerable to comsat-sweeps followed by a Wraith Salvo. Unless the protoss player uses redundant observers, the terran now has a window of opportunity to attack with impunity.

If the protoss are using Arbiters, bringing out the Valkyries (supported by Wraiths) may help, as their missiles' random-targeting seems to ignore Arbiters' cloaking fields, hitting whatever is hiding there anyway. Valkyries in large groups (eight or larger) are extremely useful against carriers and if you EMP with the science vessel, will quickly kill even a large group of carriers with minimal losses.

The science vessel is a powerful item for EMP works wonders on Dark Archons, Archons, High Templar, Shield Batteries, and Massed Carriers. However, other abilities are important as well. Defense Matrix nullifies the fragility of vultures and a squad of Matrixed Vultures can rush past a base's defenses to go straight to Probe-hunting. However, one should beware Dark Archons with Feedback.

Battlecruisers are perfect for assault due to its damage that it inflicts on its foes but the only way to counter a full fleet of Battlecruisers is by building up as many AA units as possible and also use spells to back up.