Defiler

The Defiler is a rarely encountered toxin-producing Zerg breed. Vaguely resembling a scorpion or a scantid in appearance, Defilers are veritable cancer factories. They generate a number of virus-like biochemicals which are capable of overpowering even the most effective anti-toxins. Defilers also appear to feed on other Zerg for biomaterial to produce these chemicals, and are often found with Zergling escorts. This self-destructive behavior only underscores the Zerg’s single-mindedness.

Defilers were created using DNA from all Zerg genera at the time, and resembled ambulatory Zerg larvae. Their complex genetic structure created a wide variety of acids, toxins, diseases and carcinogens which could be used to attack their enemies.

Game Unit
The Defiler draws its strength from the metasynaptic energy it creates. With that energy, the Defiler can unleash abilities like Plague and Dark Swarm that can demolish enemy forces unfortunate enough to be caught by the effects.

Despite its awesome abilities, the Defiler has a key weakness: the complete lack of a physical attack. This leaves the Defiler very vulnerable and should it be caught unescorted, even a simple Drone, SCV, or Probe can put an end to the Defiler threat. Because of this, the Defiler should always be in the company of friendly support units. If the occasion ever arises where the Defiler is alone, it should use the Burrow ability to hide and recharge its energy stores safely.

Dark Swarm

 * Starting ability
 * Energy Cost: 100
 * Function: Dark Swarm protects units in the area of effect from direct ranged attacks.

Created from a countless number of small organisms that are found on the carapace of their host, the Defiler is able to naturally send these creatures over a projected location. This leads to them forming a thick cloud of insects that swarm the location and mask it from outsiders which prevent enemy forces from accurately targeting anything within the cloud; ranged units cannot harm units protected by the cloud. Dark Swarm does not protect against melee attacks or splash damage.

Plague

 * Cost: 200\200
 * Researched at: Defiler Mound
 * Energy Cost: 150
 * Range: 9
 * Function: Plague sprays enemy units with red spores, revealing invisible units and doing up to 300 damage; however, it will not actually kill the unit, only reducing it to one hit point. It does not damage shields, only health, and it may not effect some mechanical units.

The Defiler possesses the deadly ability to produce and project a series of deadly corrosive spores that quickly destroys and corrodes anything unfortunate enough to be coated by the reddish compound. This plague does not distinguish between enemies and is equally hazardous to both units and buildings whether they are friendly or enemy. It reveals cloaked units that are caught in the initial area of effect.

Consume
The Defiler can also be evolved to include the ability to Consume other Zerg units from the same brood. Upon consumption, the Defiler regains 50 energy points, allowing it to continue to use its other abilities without having to waste the time it usually takes to wait for energy to recharge. Because the Defiler gains the same amount of energy each time regardless of the unit it consumes, the Zergling is considered the best "food" for Defilers.
 * Cost: 100\100
 * Researched at: Defiler Mound
 * Energy Cost: 0
 * Range: 1

Upgrades

 * Burrow
 * Carapace

Metasynaptic Node
Adds 50 to maximum Defiler energy.
 * Cost: 150\150
 * Upgraded at: Defiler Mound

Meserole's Plague Bearers
Meserole's Plague Bearers are powerful Defilers who serve a mercenary Brood led by Meserole the Marauder.

Thakras
Thakras is a powerful Defiler who assisted in Zerg attacks on Aridas.

Unclean One
A special hero version of the Defiler, known as the "Unclean One", can be accessed in StarEdit and played in UMS maps but is never seen in the campaign.

Zergrinch
Zergrinch is a possible non-canon Defiler who attacked Planet Christmas.

Trivia
The Defiler first appears in single-player missions in The Culling, the mission where the Garm Brood was destroyed by another Zerg force.