Colossus

The colossus was a massive protoss robotic walker designed to destroy large numbers of weaker ground targets. An antiquated construct dating back to the Kalath Intercession, it was unique among protoss automatons in that it was built purely as a war machine, in contrast to the industrial and resource-gathering automatons that made up most of the protoss arsenal. Feared even by its makers, who held that the machines could not truly be controlled and might one day turn against them, the colossus was outlawed for generations before the war against the zerg forced its return.

Design and armament#

The colossus was a towering construct that strode across the battlefield on four tall, slender legs, a configuration that gave it an extremely high level of mobility. Its great height allowed it to step up and down cliffs and other steep elevations with little difficulty and granted it a dominating field of fire, denying an enemy the advantage of higher ground. Multiple gyro-stabilizers kept the walker steady while it moved and fired. Most of its mass sat at the top of the construct, so that a colossus sufficiently damaged could topple over quickly. It was primarily powered by crystals situated between its two thermal lances.

Those lances were its weapons: one mounted on each side of the heavily armored hull, firing beams of superheated plasma that incinerated scores of enemy ground targets at once, able to reduce a group of marines to ashes in an instant. Complex focusing and targeting systems, driven by an AI and gravity-sensitive gyroscopes, analyzed target composition and predicted movement patterns so that the beams seared a path of maximum destruction with each firing cycle. The system was precise enough that a colossus could fire point blank without damaging itself. The lances suffered from limited range, a problem Khalai phase-smiths later addressed by building an extended thermal lance with enhanced airflow that operated at higher temperatures, raising beam velocity and effective range without loss of power.

The Kalath Intercession and the Conclave's ban#

The colossus was created purely as an instrument of war, and its full destructive power was demonstrated in the mass slaughter carried out against the kalathi. The killing appalled the protoss. In response, the Conclave outlawed the manufacture of colossi, and the existing machines were deactivated before being sealed away. Some were sent to distant asteroids and uninhabited moons; others were stored on Aiur, a number of them underwater, their crews and systems left dormant and awaiting a reactivation signal that did not come for generations.

The machines were not reactivated in time for the war on Aiur, as recovering and waking them would have taken too long. The war against the zerg nonetheless forced a reckoning with the old prohibition. In 2503 the protoss began collecting the sealed colossi using coordinates drawn from a preserver, despite lingering misgivings about returning such weapons to the field. In 2504 Dark Prelate Zeratul traveled to Aiur and reactivated some of the buried colossi as part of his mission to study the body of the deceased Overmind.

Tal'darim colossi and the wrathwalker#

The Tal'darim unearthed a number of colossi for themselves, drawn by the promise of superior firepower. Lower-ranking ascendants often dared one another to disable and commandeer an active colossus: success granted the daring ascendant a powerful war machine, while failure eliminated a rival. During the Second Great War the Tal'darim deployed colossi on worlds such as Xil and Atrias, and later that year used them in the defense of a xel'naga temple on Xil. Several of their machines were refitted, the thermal lance replaced with a charged pulse blaster to eliminate priority targets, and these variants were renamed wrathwalkers.

A symbol of the protoss#

By 2505 the Terran Dominion was aware of the colossi fielded by the Daelaam. Field reports referred to the walker as "a walking skyscraper of destruction" and "the tower of death," and the colossus became synonymous with the protoss in the minds of Dominion citizens. The Dominion advised its marines to find bunkers and call in air support when confronted by colossi, conceding that even soldiers who rushed underneath a walker's legs to evade its firing angles might be crushed beneath them.

The colossus served on in the conflicts that followed. In 2506 colossi were deployed in the Reclamation of Aiur to clear the warp conduits of zerg forces, and later in the End War they helped deactivate the shield around Cybros. Colossi developed under the Purifier program, built as the ultimate purification machines and employing more destructive incendiary weaponry than their Khalai counterparts, were later added to the Daelaam arsenal. In the aftermath of the End War, selected colossi that had served in the conflict were redesigned in a more traditionalist style to better resemble the ancient protoss war machines, a gesture of veneration for a weapon their makers had once feared to wield.