From Liquipedia Starcraft 2 Wiki
|Description||Capital Ship. Can build and launch Interceptors to make attacks.|
|Cost||350+100 (4 interceptors) 250 120 6|
|Attributes||Armored, Massive, Mechanical|
|Defense||300 150 2 (+1)|
Carriers are the capital ships in the Protoss air force, built at the Stargate with the Fleet Beacon as a prerequisite. Unlike other units, Carriers do not engage the enemy directly. Instead, they launch tiny Interceptors that attack in a swarm around the Carrier. The Carrier is a production facility as well; Carriers are responsible for training additional Interceptors. The Carrier initially warps in with four Interceptors available, and from there it can be ordered to train additional Interceptors (an ability that can be set to autocast) for 25 minerals each. The maximum number of Interceptors that any Carrier can hold at one time is eight. The speed with which the Carrier launches Interceptors can be improved by researching the Graviton Catapult upgrade at the Fleet Beacon.
 Attack Damage
The Carrier attack is very powerful. To understand the power of the Carrier, however, it is important to note the mechanics of the Interceptor attack. Each Interceptor fires two shots each worth 5 base damage. With a full complement of eight Interceptors, one Carrier can do as much as 80 damage in one pass. Even more staggering is the effect on the Carrier of the +1 Air Weapons Upgrade: with eight Interceptors firing two shots, a Carrier gets an amazing +16 from each Air Weapons Upgrade. On the other hand, it is important to note that the attack of the Interceptor gets decreased by 20% for every point of enemy armor because each Interceptor fires two shots. So instead of 80 damage in one pass against an enemy with 1 armor the Carrier would do 64 damage, against a unit with 3 armor it would only do 32 damage.
 Attack Range
The Carrier's range is 8, meaning that the enemy unit must be within range 8 before the Carrier will launch Interceptors at it. But after launching Interceptors, the Carrier can move back to a range of 14 before the Interceptors disengage and return to the Carrier. This allows Carriers to effectively harass mineral lines, and with careful micro, the Carrier can even effectively engage air superiority fighters like the Viking.
It should be noted that, unlike most air units, Carriers cannot be kited by Vikings, and though in general Vikings will defeat Carriers cost for cost, a Carrier will defeat 3 Vikings, which costs almost as much as a Carrier, since it will take down Viking by Viking, reducing the damage it is getting hit with, while still hitting at full power itself. A fully loaded Carrier can kill a Viking in two hits, due to Vikings being an unarmored unit. With 3 attack upgrades, a Carrier can kill a non-upgraded Viking in one hit.
 Competitive Usage
 Current use in competitive play
Currently, Carriers are not widely seen in SC2 due to the inability of any build to safely transition to them. Though Carriers do not yet have a solid position in SC2 competitive play, they are extremely powerful versus stationary defenses and AI controlled units, since the AI will target the individual Interceptors first, not the Carriers themselves.
 Vs. Protoss
Generally speaking Carriers are not very good in Protoss vs. Protoss because they are easily countered by Stalkers + Sentries. Carriers can be used to counter Void Ray heavy builds together with Phoenixes since player with Void Rays will usually try to focus down the Carriers, therefore allowing Phoenixes to score free hits and decimate Void Ray army. Carriers should use hit and run tactics against them.
Once the late-game hits, Carriers and Void Rays can be an extremely powerful unit composition since Stalkers will get decimated by Void Ray's bonus damage to armored units once Carriers and Void Rays hit a critical mass. However one should be aware of Tempest + Void Ray composition since Tempests can snipe Carriers before they can do any harm. Also Tempests have lower supply cost than Carriers.
 Vs. Terran
Vikings, while killed in 2 volleys by Carriers, are less than a third of the cost, and while one Carrier will defeat 3 Vikings, this is the only match-up where the Carrier wins cost-for-cost: 4 Vikings will defeat one Carrier, and 6 Vikings will defeat 2 Carriers if they focus their fire. Vikings are a very soft counter, though and can't kite Carriers after Interceptors grab a target, so with appropriate micro, Carriers can stay competitive. Marines can't out range a well placed Carrier (besides getting shredded by the Carrier's improved targeting AI), though if they can get within range, cost-for-cost, Marines are also a good defense. Terrans have the best options for killing Interceptors, so careful management of your squadrons is key.
Beware of heavy AA emplacements. A location fortified with Marines and Missile Turrets can quickly turn Interceptor squadrons into dust. Interceptors no longer recover max health between sorties as they did in Brood War, and while large numbers can withstand a serious beating overall, they will not last long enough to break a sustained anti air defense.
Be cautious of flying structures. Carriers will automatically launch Interceptor squadrons at targets in range, and clever Terrans may use this to tease your Interceptors into a hail of gunfire at minimal risk.
Battlecruisers are extremely dangerous to contend with. With 3 base armor, a Battlecruiser with equal upgrades takes 40% damage from Interceptors, and will wipe out a full squadron in half the time you need to take one down. Attempting to kill Battlecruisers with Interceptors can turn into a huge mineral drain that leaves your Carriers vulnerable. To top it off, a well placed Yamato Cannon can severely damage or kill your Carriers outright, making it a bad idea to go toe to toe against a Terran victory fleet.
Carriers are very powerful against a Terran that is going for a mechanical composition (which includes primarily Hellions, Siege Tanks, Thors, and Banshees). Carriers, if unscouted, supplement a typical Protoss composition very well because of the lack of anti-air in the Terran's army. However, it scouted, Vikings will almost definitely be made as a direct counter, so it is important to not over-commit to Carriers in this type of situation, and use them to either destroy the Terran army and/or to force an overproduction of Vikings.
 Vs. Zerg
Carriers can be used as an all-in in PvZ. Off of a Forge Fast Expand, if Carriers are made from hidden Stargates, the opponent can be caught significantly off-guard and immediately lose the game if not adequately prepared with anti-air.
Carriers with weapons and launch upgrade can be effective against Zerg if the Zerg player is not prepared to counter with Corruptors. Corruptors are a very strong unit against a Carrier, but they can be effectively kited due to a Carrier's superior range. Hydralisks can also be a problem as they are good at taking down Interceptors quickly. Hydralisks are not a large threat to Carriers, however, due to their slow movement speed and extremely low hit points.
The Carrier's role is primarily to force Corruptors from a Zerg and to add extra damage. Making several Carriers in late-game PvZ can cause the Zerg to overcompensate in Corruptors, because of the difficulty in knowing exactly how many Carriers the Protoss wants to make, and how many Corruptors to make per Carrier. Do note however that if a ground transition is made by the Protoss after the Carriers are killed the remaining Corruptors can be morphed into Brood Lords, which may pose a serious problem if you are not adequately prepared for them.
In conjunction with Archons and the Mothership, Carriers will decimate the Zerg's late-game Brood Lord/Infestor/Corruptor army composition. Carriers can easily pull back to the cover of the Archons while Corruptors try to focus fire on the Carriers and Mothership. Due to the AI, the Corruptors will stack up quite a bit when focusing the Carriers, thus rendering them susceptible for insane amounts of Archon splash damage. Once the Corruptors are dead, Brood Lords will fall along with the Infestors.
Carrier's quotes (video and sound) - YouTube video.
- Carrier rush was the object of Day Daily #188.
- The song Mr. Lonely (Sc2 Carrier Parody) laments that this unit is so unused in comparison to how much use it saw in Starcraft 1.