Within the Dominion Armed Forces, whenever a strike force is deployed planetside, the engineering bay is one of two key research facilities to be established in a field base as soon as possible (the other being the armory), improving the quality of infantry weapons.[2] During the Great War, these structures were equipped with the ability to lift off and move to a new location. However, after the Brood War, the engineering capabilities were improved, increasing the personnel of the structure and intricacy of their work. Because of this, engineering bays were no longer cleared for flight.
The Dominion Special Forces utilize AIs in their experimental engineering bays, which increase their research speed by fighting each other in simulated battles. Meanwhile, a portion of the Knights of Tyradors engineering bays are utilized in researching new amusement park attractions, though this was temporarily suspended after the Battle of Tyrador IX.[3]
The weapons plant was a terran structure in the StarCraft beta. It was cancelled before the game's full release.[4] It was later turned into the engineering bay.[5]
Attack upgrades improve attack cooldown of affected units by 5% per level.[6]
These self-replicating ultra capacitors reduce the reload time of weapons and systems. Now each of the weapon upgrades at the armory and engineering bay increases attack speed by 5% in addition to increasing damage.
Armor upgrades increase health of affected units by 5% per level.[6]
We have created a new lightweight alloy called vanadium. Vanadium diffuses weapon impacts much more efficiently than traditional armor plating, and it better preserves the life of our units. Now each of the armor upgrades in the armory and engineering bay increases unit life by 5% in addition to increasing armor.
All structures repair themselves to 50% life. All structure fires are automatically put out.
This all-in-one safety system automatically dispatches robotic drones to put out any fires and perform basic repairs on damaged structures. Although these drones are effective at doing basic repairs, they do not have a strong enough AI to perform the more delicate repairs needed to restore a structure past half life.[7]
Notably Swann and Han and Horner's engineering bays do not give them infantry weapon or armor upgrades; the building gives Swann defensive turret and building upgrades only, while Han and Horner gets special upgrades for Mira's infantry units instead. Han and Horner weapon and armor upgrades are provided at their armory instead. Alexei Stukov has access to a infested engineering bay which can upgrades infested infantry and infested bunkers.
100 Mastery: -2 per Research Resource Cost mastery point. Down to a minimum 40 100 Mastery: -2 per Research Resource Cost mastery point. Down to a minimum 40 160
Level 2
Cost
175 Mastery: -3.5 per Research Resource Cost mastery point. Down to a minimum 70 175 Mastery: -3.5 per Research Resource Cost mastery point. Down to a minimum 70 190
Level 3
Cost
250 Mastery: -5 per Research Resource Cost mastery point. Down to a minimum 100 250 Mastery: -5 per Research Resource Cost mastery point. Down to a minimum 100 220
Vanadium Plating: Increases the life of terran infantry by 10% per level.
Backwater Marshall: The increase of life for terran infantry go up, from 10% per level to 20% per level.
Usage
Passive
Campaign Acquisition
Unlock
Initially available.
Acquisition
Purchased from
Engineering bay
Hotkey
A
Level 1
Cost
100 Mastery: -2 per Research Resource Cost mastery point. Down to a minimum 40 100 Mastery: -2 per Research Resource Cost mastery point. Down to a minimum 40 160
Level 2
Cost
175 Mastery: -3.5 per Research Resource Cost mastery point. Down to a minimum 70 175 Mastery: -3.5 per Research Resource Cost mastery point. Down to a minimum 70 190
Level 3
Cost
250 Mastery: -5 per Research Resource Cost mastery point. Down to a minimum 100 250 Mastery: -5 per Research Resource Cost mastery point. Down to a minimum 100 220
Bunkers gain +2 capacity and command centers gain +5 capacity.
Usage
Passive
Campaign Acquisition
Unlock
Initially available.
Acquisition
Purchased from
Engineering bay
Hotkey
N
Cost
100 Mastery: -2 per Research Resource Cost mastery point. Down to a minimum 40 100 Mastery: -2 per Research Resource Cost mastery point. Down to a minimum 40 60
100 Mastery: -2 per Research Resource Cost mastery point. Down to a minimum 40 100 Mastery: -2 per Research Resource Cost mastery point. Down to a minimum 40 60
Reduces the cooldown of Reapers KD8 Charge by 10. When Reapers are killed, they throw 8 grenades at the killing unit (deals 5 damage per grenade within a radius of 1.5).
Stronger Death Chance Mastery: When Reapers are killed, they throw 15 grenades at the killing unit (deals 5 damage per grenade within a radius of 1.5) with a 1.5% chance per mastery point.
Chaotic Power Couple: Increases the damage dealt by grenades from slain Reapers from 5 to 10.
Usage
Notes
Mastery: +1.5 chance per Stronger Death Chance mastery point. Up to a maximum 45% chance
Reduces Sentinel Missile cooldown by 20 seconds. When Widow Mines are destroyed, they launch 5 Sentinel Missiles at random nearby targets (within a radius of 5.5) that deal 10 (20 vs. Shields) area damage (radius 2.625).
Stronger Death Chance Mastery: When Widow Mines are destroyed, they launch 10 Sentinel Missiles at random nearby targets (within a radius of 5.5) that deal 10 (20 vs. Shields) area damage (radius 2.625) with a 1.5% chance per mastery point.
Chaotic Power Couple: Increases the damage dealt by Sentinel Missiles from destroyed Widow Mines from 10 (20 vs. Shields) to 20 (30 vs. Shields).
Usage
Notes
Mastery: +1.5% chance per Stronger Death Chance: mastery point. Up to a maximum 45% chance
Hellions and Hellbats transform 75% faster. When Hellions are killed, nearby allied units in a radius of 3.5 gain 25% movement and 15% attack speed for 15 seconds.
Stronger Death Chance Mastery: When Hellions are killed, nearby allied units in a radius of 3.5 gain 50% movement and 30% attack speed for 15 seconds with a 1.5% chance per mastery point.
Chaotic Power Couple: Increases the Aerosol Stim Emitters movement and attack speed bonuses from 25% and 15% (50% and 30% with Stronger Death Chance Mastery) respectively to 50% and 30% (100% and 60% with Stronger Death Chance Mastery) respectively.
Usage
Duration
15
Notes
Mastery: +1.5% chance per Stronger Death Chance: mastery point. Up to a maximum 45% chance
Hellions can launch a bomb that deals 20 damage to the target unit. Nearby enemies have their movement speed reduced by 75% and attack range reduced by 3 for 5 seconds. Can be set to autocast.
Hellbat movement speed is increased by 50%. When Hellbats are killed, they ignite the surrounding area (radius 4). Enemies in the fire run around in fear for 3 seconds.
Stronger Death Chance Mastery: When Hellbats are killed, they ignite the surrounding area (radius 5.66) with a 1.5% chance per mastery point. Enemies in the fire run around in fear for 3 seconds.
Chaotic Power Couple: The duration of the Hellbat death effect is increased by 100%.
Usage
Duration
3 6 (with Chaotic Power Couple)
Notes
Mastery: +1.5% chance per Stronger Death Chance: mastery point. Up to a maximum 45% chance
As of patch 4.7.1, Neosteel Frame and Structure Armor were merged into an upgrade called Neosteel Armor.
The StarCraft II engineering bay was designed to be a more simple structure than its predecessor. It was decided to make it a grounded structure as per the belief that only unit-producing structures should be able to lift off.[8]
