Hydralisk den

The Zerg Hydralisk Den bears only a passing resemblance to the nests of the once peaceful Slothien that the Hydralisks evolved from. Containing Hydralisk genetics, the structure allows Larvae to morph into Hydralisks. Also, to help along the evolution of the Hydralisk, the Hydralisk Den can also provide the genetic code necessary for Muscular Augments (faster movement), Grooved Spines (longer range) and the Lurker Aspect (allows Hydralisks to morph into Lurkers).

StarCraft II
The Hydralisk Den is set to appear in StarCraft II. It unlocks the Hydralisk. It can mutate into a Deep Warren, enabling Lurkers to be developed.

The Hydralisk has been moved to tier 1.5. This suggests a change in the requirements for the Hydralisk Den.

Evolution
Deep Warren
 * Mutation Cost: 50 150  40 seconds
 * Enables the Hydralisk Den to transform into a Deep Warren, enabling Hydralisks to transform into Lurkers.