Forbidden Weapon is a mission in the campaign of Legacy of the Void, and the first mission in the Purifier storyline. Unlike the other two story arcs, it is a single mission that has a storyline continued later in the campaign.[1]



"Within the Glacius facility, the Purifier program has been reborn. We must recover this immensely powerful technology."

- Hierarch Artanis(src)

In his time as Hierarch, Artanis was made aware of a program by the Khalai Caste to create new Purifiers upon the world of Glacius. Artanis sought this technology to turn the tide against Amon's forces, but when he arrived there he found the Tal'darim death fleet already in orbit attacking the Glacius facility.


TechnologyVault SC2-LotV Game1

Purifier Technology vault on Glacius

As the Daelaam forces arrived at the planet, they were greeted by First Ascendant Alarak, who stated they were too late and the facility would be destroyed. His Tal'darim mothership unleashed its displacement beam and began to destroy the facility's defenses, advancing on the technology vault.

Phase-smith Karax activated the facility's defensive sentries, and added them into the Spear of Adun's warp matrix. Daelaam forces quickly engaged the Tal'darim, staying ahead of the mothership's beam. Several caches of raw solarite were uncovered in the facility, left behind by the scientists there.

Artanis's forces reached the vault and deactivated its shields just in time, allowing the Spear of Adun to warp aboard the container holding the data on the Purifier program. Karax discovered a prototype warrior within the container.


"Artanis! It is good to see you, young Executor!"

- Purifier prototype with the memories of Fenix(src)

Aboard the Spear of Adun, Karax discovered that the Purifier prototype was a robotic construct with the encoded memories of Praetor Fenix. It was not aware it was a Purifier or that the real Fenix had died, and its last memories were of Judicator Aldaris ordering him to Glacius and putting him in stasis. Artanis, though relieved to see his old friend again, was not entirely sure if it was truly Fenix, and noted he served as a melancholy reminder of his death.


The player spawns on the southeast corner of the map, and must race against the Tal'darim's displacement beam to get to the technology vault. A balanced force of stalkers and zealots can break through most defenses, as long as there is a strong economy supporting the force. As the mission goes on, force field barriers can be destroyed to allow quicker reinforcement, or pylons can be warped in close to the frontline to allow for quick warp ins.

When engaging Tal'darim bases, try to bait out forces from behind their static defenses before engaging, and engage only portions of their defense at a time. Though the bonus objectives are not that well defended, they can be hard to find in the time allotted, so it may be worth it to save before the final attack on the vault, scout the map, and reload once it is known where the solarite is.

The final objective only requires the destruction of the pylons next to the technology vault, so if running out of time the player can dive in forces to destroy them and still win the mission.

UnrestrictedAccess SC2-LotV Screenshot

Solar Lance can destroy the pylon through the field.

The mastery achievement leaves very little time to spare, if the player traverses the map in the conventional manner. However, there is an exploit that saves a considerable amount of time. A force field on the left side of the map (The plateau where the first raw solarite is stored) has a pylon normally inaccessible without going through several other force fields and Tal'darim forces. However, the player can use the Spear of Adun's Solar Lance ability to strike through the force field. If the player uses Solar Lance's three charges to hit the pylon all at once, the pylon will be destroyed and the force field will come down, saving the player having to go through a significant part of the level.

Another advantage in this level is the annihilator. When the player is alerted to warp prisms flying in (which occurs near the base behind the above force field), the player can use the annihilators' Shadow Cannon to focus down the prisms and destroy them, considerably weakening the Tal'darim defenses. Four prisms fly in, so the player will need four annihilators to destroy them all. Also, annihilators can focus down priority targets like carriers and colossi (and, on Brutal difficulty, wrathwalkers), making them a necessity to advance in higher difficulties.

Starcraft 2 - FORBIDDEN WEAPON - Brutal (Achievements) LOTV 8

Starcraft 2 - FORBIDDEN WEAPON - Brutal (Achievements) LOTV 8.


ForbiddenWeapon SC2-LotV AchieveIcon1 Forbidden Weapon

10 Achievement SC2 Game1


Complete the "Forbidden Weapon" mission in the Legacy of the Void campaign.

ForbiddenWeapon SC2-LotV AchieveIcon2 Pull The Plug

10 Achievement SC2 Game1


Destroy 6 Tal’darim Gateways or Warp Gates in the “Forbidden Weapon” mission on Normal difficulty.

ForbiddenWeapon SC2-LotV AchieveIcon3 Danger Zone

10 Achievement SC2 Game1


Don’t let the Tal’darim Displacement Beam destroy any of your units in the “Forbidden Weapon” mission.


The achievement name is a reference to the Kenny Loggins song Danger Zone.

ForbiddenWeapon SC2-LotV MasteryAchieveIcon Unrestricted Access

10 Achievement SC2 Game1


Reach the Technology Vault in less than 11 minutes in the “Forbidden Weapon” mission on Hard difficulty.