Unsealing the Past

Unsealing the Past is a mission in the campaign of Legacy of the Void, and the second mission in the Purifier storyline.

Background
""History has shown the Purifiers cannot be controlled." "They do not have to be. These personalities, like I, will have free will"

- Fenix and Rohana

After some deliberation, Artanis decided that the ancient Purifiers who had been sealed away on Cybros needed to be reactivated. He thought that with some convincing, they would help him in the war against Amon just as Fenix had. Rohana was vocally opposed, but Artanis went ahead with the operation.

Cybros was in orbit above the forest planet of Endion. On the surface several statis locks shielded the platform, and would have to be deactivated in order to reactivate the purifiers. Unfortunately, a large contingent of Amon's zerg broods had infested the planet.

Mission
Artanis and his forces arrived on the surface to deactivate the stasis field generators. Karax discovered the locks could only be unsealed through a device called the Megalith, which would have to be guided to each stasis lock. Unfortunately, the forests were infested with zerg. Karax activated the facility's colossi in order to cover the Megalith as it moved.

Karax uncovered several power cores of incredible size, constructed with solarite components, that would be value for the Spear of Adun's solar core. The Daelaam forces pushed through reinforcing zerg numbers, but eventually the Megalith was escorted to the last lock, freeing Cybros from stasis. Artanis recalled his forces and made his move to Cybros.

Walkthrough
The goal of this mission is to escort the Megalith to the stasis locks, through heavy zerg defenses. The Megalith is not unarmed, and will fire thermal lances at any zerg it comes across. However, it is still fragile, and cannot be path blocked, so even if the player lacks forces it will move on without them.

Colossi are the key to this mission, as is using their ability to scale cliffs and attack out of range of the zerg. However, colossi are fragile, and other forces are necessary to provide a buffer for them. The bonus objectives are moderately well defended and may take some effort to get, so it is best to wait until the Megalith is in stasis before going after them.