Raging storms, Endless Plagues, Fire in the sky,

In the history of sentinence, these disasters were often seen as signs of:

Divine Retribution, the Apocalypse, the end of everything,

They are not even close...

When the Xel'Naga were nearing the end of their cycle, the search for suitable species for the next one began. During that time, there was talk of a prophecy fortelling of their destruction and the return of a ancient darkness long cast away. Some refused to believe it, while others accepted it as inevitable and began preperations in the hopes of ending the darkness once and for all.

One of these individuals was in charge of planetary development. Through this Xel'Naga's work came the creation of the Vaul artificial intelligence. Originally intended for scouting worlds and seeding them with life, the maverick Xel'Naga placed hidden protocols within the Vaul that would be triggered after receiving a special signal.

What this program is and what it will mean for the first-born, second-born, and everything else is unknown. Only time will tell wheither or not the plan succeeds.


Golden AgeEdit

Prior to the discovery of the Protoss, the first Xel'Naga robots created were used in exploration, resource mining, medical research, and defence. Due to the lack of any enemies of equal power to oppose them, the Xel'Naga leaned towards more science-based robots and the combat series were send to cold storage.

First BornEdit

When they had reached the ultimate stage of evolution, they began their search for the perfect race to carry on their legacy. Thus, they created the Heralds and sent them across the universe searching for worthy species.

Finally, one Herald came upon Aiur. Seeing that the dominate species fit one of the three primary traits of their objectives, purity of form, It signalled for the Xel'Naga to come (Marvel: Silver Surfer). Having finished its primary objective, the Herald continued its search for more worthy races.

After the Xel'Naga left the Protoss, some of their scientist felt it too soon to leave the Protoss unsupervised, so they set advanced observation droids to watch over their first creations.

Second AttemptEdit

Due to the limited, but adaptive, A.I. of the Heralds, they continued their search for new races without knowing of the Protoss failure. A Herald soon came to Zerus and found the Zerg. Fullfilling the Secondary objective, purity of essence, the Heralds once again signalled for the Xel'Naga to arrive.

Satisfied with the results of their experiments, the scientists sent the Heralds to the homeworld and other research bases to standby for further instuctions.


For eons the robots slumbered growing their A.I. into actual conciousness, until a Xel'Naga beacon was activated on Bhekar Ro (Starcraft: Shadow of the Xel'Naga). After receiving data from the phoenix entity, the robots learned the Xel'Naga's fate, the existence of another new race in the Koprulu Sector and began preperations for the next phase of the Plan.

Units and BuildingsEdit


  • Created by the Xel'Naga, but not a chosen race (Protoss/Zerg)
  • Terran < Strength/HPs/Shield Points < Protoss
  • Tactics and Strategies: United they stand, Divided enemies will fall
  • Special abilities: Compatible with other technology and Interface for more power (potential to be stronger than Protoss)
  • Construction color: Dark Blue (Starcraft Brood War: Shakuras Temple)
  • All Vaul units and buildings are robotic just as all Zerg units and buildings are biological
  • Adviser/Commander: Operator (Terran - Adjunct, Zerg - Cerebrate, and Protoss - Judicator)

See list of Vaul Units

See list of Vaul Buildings


Xel'Naga technology is the most advanced of all known races. Planets and Galaxies would fall with a scrap of this knowledge. Even by Protoss standards, it is treated with mythological reverence. As the Vaul are Xel'Naga tech, they understand it better than any other existing race save the creators themselves.

Learning how powerful the two chosen races developed is one of the reasons why the Vaul never sought open conflict. The second reason is that all other traces of Xel'Naga technology hidden across the universe and constructing new equipment would draw unwanted attention. This forced the Vaul to make due with whatever technology they could aquire through stealth.

Since Vaul A.I.s are software, they can move from computer to computer exchanging information in a collective conscience imitating the Zerg Overmind (Terminator: SkyNet). When one is defeated, the A.I. rejoins the collective to be reborn like Zerg Cerebrates (Stargate Atlantis: Asuran; Mass Effect: Geth). The difference is their A.I.s can preform individual thought like the Protoss and Terrans (Beast Machines: Vehicon general). As a result, they can also cut themselves off from the collective if the unit becomes compromised, such as when Zeratul and the Overmind became temporarily linked.

The only set back to the Vaul's hybrid tech is that a skilled technician could reprogram the components they recognize. This risks Vaul forces turning on each other. As a precaution, the pure Xel'Naga technology forces are held in reserve until needed.