Loads infantry into [Bunker](/starcraft-2/unit/Bunker).

Load

Unload All

Salvages the structure, removing it and returning 75% of its mineral and gas value. Salvage takes 4 seconds to finish. Warning: once Salvage is triggered, it cannot be canceled.

Salvage

Loads nearby [SCVs](/starcraft-2/unit/SCV) into Command Center.

Orders selected units to holster their weapons and avoid engaging enemies, unless given a direct command. Units holding fire will flee if attacked.

Hold Fire

Decloaks the selected unit, making it visible to enemies.

Decloak

Orders selected units to fire at will. They will engage enemy units within range and chase them as normal.

Weapons Free

Orders [MULE](/starcraft-2/unit/MULE) to gather minerals from a selected Mineral Field.

Gather

Returns the carried resources to the nearest drop-off point.

Return Cargo

Restores life to mechanical units and structures at the cost of resources.

Repair

Loads units into the [Medivac](/starcraft-2/unit/Medivac)'s hold.

Orders [SCV](/starcraft-2/unit/SCV) to gather resources from a selected Mineral Field or Vespene Geyser.

Orders the unit to apply your currently selected spray to the terrain at the target location.

Spray

Heals a friendly biological target.

Heals 13 life per 1 energy.

Heal

Arms the Silo with a Tactical Nuke.

Nukes take 14 seconds to land, but they deal up to 300 (+200 vs. structures) damage in a large radius.

Use a [Ghost](/starcraft-2/unit/Ghost) to designate the target.

Arm Silo With Nuke

Prototype harvesting unit. Gathers minerals more quickly than regular [SCVs](/starcraft-2/unit/SCV). MULEs last 64 seconds before their systems fail.

MULE

Drops an experimental robotic [MULE](/starcraft-2/unit/MULE) miner onto the target Mineral Field. [MULEs](/starcraft-2/unit/MULE) collect minerals more quickly than [SCVs](/starcraft-2/unit/SCV).  

MULEs last 64 seconds before their systems fail.

Calldown: MULE

Sniper. Can use Snipe, EMP Round, and be upgraded to use Cloak. Can call down Tactical [Nukes](/starcraft-2/unit/Nuke) built at the Ghost Academy.

Can attack ground and air units.

Ghost

Heavy assault infantry.

Can attack ground units.

Marauder

Enables [Marines](/starcraft-2/unit/Marine) and [Marauders](/starcraft-2/unit/Marauder) to use the Stimpack ability. Stimpacks cause damage to a unit, but they increase its attack and movement speeds for a short time.

Stimpack

[Marines](/starcraft-2/unit/Marine) gain +10 life.

Combat Shield

Upgrades the [Marauder](/starcraft-2/unit/Marauder) weapons to slow down opponents.

Concussive Shells

Adds +1 range to [Auto-Turrets](/starcraft-2/unit/AutoTurret), [Missile Turrets](/starcraft-2/unit/MissileTurret), [Planetary Fortresse](/starcraft-2/unit/PlanetaryFortress)s, and Point Defense [Drones](/starcraft-2/unit/Drone).

Hi-Sec Auto Tracking

Neosteel Armor

Upgrades the damage dealt by infantry units.

+1 Infantry Weapons

Further upgrades the damage dealt by infantry units.

+2 Infantry Weapons

Maximizes the damage dealt by infantry units.

+3 Infantry Weapons

+1 Infantry Armor

Further upgrades the armor of infantry units.

+2 Infantry Armor

+3 Infantry Armor

Upgrades the damage dealt by ground vehicles.

+1 Vehicle Weapons

Further upgrades the damage dealt by ground vehicles.

+2 Vehicle Weapons

Maximizes the damage dealt by ground vehicles.

+3 Vehicle Weapons

Upgrades the damage dealt by units built at a Starport.

+1 Ship Weapons

Further upgrades the damage dealt by units built at a Starport.

+2 Ship Weapons

Maximizes the damage dealt by units built at a Starport.

+3 Ship Weapons

Upgrades the armor of units built at a Factory or Starport.

+1 Vehicle and Ship Plating

Further upgrades the armor of units built at a Factory or Starport.

+2 Vehicle and Ship Plating

Maximizes the armor of units built at a Factory or Starport.

+3 Vehicle and Ship Plating

Improves the [Hellion](/starcraft-2/unit/Hellion)'s Infernal Flamethrower to deal +5 damage vs. light units.

Does not affect [Hellbat](/starcraft-2/unit/HellionTank).

Infernal Pre-Igniter

Allows [Widow Mines](/starcraft-2/unit/WidowMine) to burrow and activate three times as fast.

Drilling Claws

Allows [Hellions](/starcraft-2/unit/Hellion), [Hellbats](/starcraft-2/unit/HellionTank), Vikings, [Liberators](/starcraft-2/unit/Liberator) and Thors to transform quickly between combat modes.

Smart Servos

Mobile assault vehicle. Can use Lock On to quickly fire while moving.

Can attack ground and air units.

Cyclone

Heavy tank. Can switch into Siege Mode to provide long-range artillery support.

Can attack ground units.

Siege Tank

Heavy assault mech.

Can attack ground and air units.

Thor

Enables use of the [Battlecruiser](/starcraft-2/unit/Battlecruiser) Yamato Cannon.

Weapon Refit

Increases the range of [Liberators](/starcraft-2/unit/Liberator) in Defender Mode by 4.

Advanced Ballistics

Increases the energy regeneration rate of [Medivacs](/starcraft-2/unit/Medivac) by 100%.

Caduceus Reactor

Enables [Ghosts](/starcraft-2/unit/Ghost) to use the Cloak ability. Cloak renders a unit invisible to enemies unless it's revealed by detectors or effects.

Personal Cloaking

Enables [Banshees](/starcraft-2/unit/Banshee) to use the Cloak ability. Cloak renders the Banshee invisible to enemies unless the unit is revealed by detectors or effects.

Cloaking Field

Allows [Ravens](/starcraft-2/unit/Raven) to use the Interference Matrix ability.

Interference Matrix

Increases the movement speed of [Banshees](/starcraft-2/unit/Banshee).

Hyperflight Rotors

Tactical-strike aircraft. Can be upgraded to use cloak.

Can attack ground units.

Banshee

Powerful warship. Can use Yamato Cannon and Tactical Jump.

Can attack ground and air units.

Battlecruiser

Aerial support unit. Can use [Auto-Turret](/starcraft-2/unit/AutoTurret), Point Defense [Drone](/starcraft-2/unit/Drone), and Seeker Missile.

Detector

Raven

SCV Scout

Send Reaper to scout opponent's main base.

Reaper Scout

Primary structure. Used to receive gathered resources. Can use the Lift Off ability and can upgrade into an Orbital Command or a [Planetary Fortress](/starcraft-2/unit/PlanetaryFortress).

Enables:
- [SCVs](/starcraft-2/unit/SCV)

Command Center

Transforms structure into a slow air unit for redeployment. May not produce units, research upgrades, or use abilities until it has landed.

Command Center Lift Off

Primary structure. Must land to receive resources, produce units, or use abilities.

Command Center (Flying)

Lands the structure at a target location, allowing it to once again produce units, research upgrades, and use abilities.

Command Center Land

Upgrades Command Center to a [Planetary Fortress](/starcraft-2/unit/PlanetaryFortress), greatly increasing its armor and arming it with a powerful defensive turret. Cannot lift off.

Can attack ground units.

Upgrade to Planetary Fortress

Upgrades Command Center to an Orbital Command, unlocking Scanner Sweep, Calldown: [MULE](/starcraft-2/unit/MULE), and Calldown: Extra Supplies. Cannot load [SCVs](/starcraft-2/unit/SCV).

Upgrade to Orbital Command

Primary structure. Used to train [SCVs](/starcraft-2/unit/SCV) and receive gathered resources. Can use the Scanner Sweep ability. Can use the abilities Calldown: [MULE](/starcraft-2/unit/MULE) and Calldown: Extra Supplies.

Orbital Command

Orbital Command Lift Off

Orbital Command (Flying)

Orbital Command Land

Drops additional supplies, permanently increasing the supply output of the target [Supply Depot](/starcraft-2/unit/SupplyDepot) by 8.

Supply Drop

Reveals an area of the map, detecting cloaked and burrowed units. Lasts 9 seconds.

Scanner Sweep

Infantry-production facility.

Enables:
- [Marines](/starcraft-2/unit/Marine)
- [Reapers](/starcraft-2/unit/Reaper)
- [Bunkers](/starcraft-2/unit/Bunker) from [SCVs](/starcraft-2/unit/SCV)
- Orbital Commands from Command Centers

Barracks

Barracks Lift Off

Barracks must land to start unit production.

Barracks (Flying)

Barracks Land

Vehicle-production facility. 

Enables:
- [Hellions](/starcraft-2/unit/Hellion)
- [Widow Mines](/starcraft-2/unit/WidowMine)

Factory

Factory Lift Off

Factory must land to start unit production.

Factory (Flying)

Factory Land

Air-unit production facility. 

Enables:
- Vikings
- [Medivacs](/starcraft-2/unit/Medivac)

Starport

Starport Lift Off

Starport must land to start unit production.

Starport (Flying)

Starport Land

Allows 2 units to be created simultaneously.

Reactor (Barracks)

Enables additional units and research options. A Tech Lab can fit onto any production structure.

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