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The cost of a special ability is the amount of energy required to cast it while the research cost is the amount of resources (minerals and gas) need to make it available.

[edit] Burrow

Allow the unit to burrow itself to hide from enemies. A burrowed unit can only be seen by a detector unit.

Statistics

Cost: None

Research cost: 100/100

Research building: Lair, Hive

Available for: Drone, Zergling, Hydralisk and Defiler

[edit] Consume

Allow to sacrifice a friendly Zerg unit to regain energy. Consume is a defiler ability. It can be used on burrowed units as well as on eggs but not on larvae.

Statistics

Cost: None

Research cost: ?

Research building: Defiler mound

Available for: Defiler

[edit] Dark swarm

Create a cloud (6x6) where ranged attacks have no effect. The cloud last 60 seconds. Melee and splash damages are not affected.

Statistics

Cost: 100

Research cost: ?

Research building: None

Available for: Defiler

Range: 9