Viper

The viper is a new strain of zerg fliers being incorporated in the upcoming expansion StarCraft II: Heart of the Swarm. They are lair-level units that apparently have no pre-requisite building, and replace the overseer as a support caster and detector for the swarm. The viper has three abilities:


 * Ocular Parasite: The viper grants detection to an allied non-massive unit. The viper can target other vipers or itself with this ability. It can only be used once.


 * Abduct: The viper targets a unit and pulls that unit to the viper's location. This allows it to pull allies to safety, or pull enemy units out of position. The ability can pull units up and down cliffs.


 * Blinding Cloud: The viper spits a green cloud. Ranged units in the cloud have their ranged reduced to one. Units can move out of the cloud to fire normally.

As of April 2012, the viper can also "eat" minerals in order to recover energy. This renders the patch unavailable, so it should not be used in the player's base.

Development
The concept of the viper goes as far back as 2008. It resembled a snake/scorpion in this form. Concepts were done by Samwise Didier.