Evolution chamber

The zerg evolution chamber is the result of the Overmind's view that complacency is the road to defeat, causing it to spur zerg evolution constantly. The evolution chamber provides a testing ground for the genetic code of lesser breeds, helping to increase the offensive and defensive capabilities of the zerg ground-based breeds. It is also required in order for a creep colony to mutate into a spore colony.

The base of the evolution chamber forms from the genetic template of an unknown creature. During development, the "chamber" grows around a full skeleton with a skull, spinal column and ribs, that falls apart when the pit is destroyed. The biological roots of this creature is still unknown to terran scientists.

The evolution pit contains a hardened skin that grants it near immunity to small arms fire, as well as genetic transmission appendages that allow it to transmit genetic information to other structures of the hive cluster.

The evolution chamber, in the form of the evolution pit, is also found within leviathans.

Development
Unlike its alpha appearance, the evolution chamber's form in the StarCraft beta was mostly identical to its end version, though had a distinctly more withered appearance.

StarCraft II
The evolution chamber appears in StarCraft II. When attacked and destroyed it appears to have a basic skeleton structure that falls out; containing a head, spinal column, and ribs.

Heart of the Swarm
The evolution chamber, in the form of an evolution pit, appears as its own environment in Heart of the Swarm. Zerg evolution is driven here in regards to upgrades and unit choices.

Co-op Missions
Kerrigan, Zagara and Abathur can unlock various upgrades at the evolution chamber. Zagara and Kerrigan upgrade themselves, Zagara also has aberration upgrades, and Abathur researches swarm queen upgrades.

Development


The evolution chamber has undergone numerous changes during the development of StarCraft II.