Whenever expected because of the Admiral Whitcomb as to why on her tips, she gave a straightforward UNSC password “Three-Nine-One or two,” and therefore created that she are to the a leading top priority mission
Dr. She volunteered to stay trailing so as that the UNSC technology is actually covered regarding you can easily get. [20] She started Procedure: Light GLOVE, sooner or later ruining several AIs (and Cortana’s “elderly sibling” Kalmiya) to save the newest Covenant out of opening UNSC databases. On the expectation the Covenant manage cup the entire world, together with training you to definitely regardless if they didn’t, she’d end up being against a whole armed forces regarding Covenant surface forces, Halsey is actually ready to sacrifice their work.
With her Spartans, Halsey exhausted Palace Ft, moving deeper for the shafts less than
Although not, it changed whenever Spartans Fred-104, Kelly-087, Vinh-030, Isaac-039, and will-043 checked from the entry to Castle Feet. Towards firepower to probably challenge their way out, enduring Castle Base’s exhaustion became feasible. She provided crisis assistance into the Spartans due to their injuries, however, a document anomaly recognized by this lady associated AI, Kalmiya, drawn Dr. Halsey’s interest.
The content ended up being accessed of the Araqiel, a keen AI you to definitely struggled to obtain Colonel Ackerson, one of Dr. Halsey’s chief opposition contained in this ONI. Once tracing the content supply, Dr. Halsey stumbled across the newest AI, deserted by its learn. Araqiel up coming endangered this lady, supposed as much as to inform her he would complete the fresh new space with poison, and that she’d feel reported. In reaction, Halsey entered archaic line commands – the bottom code undergirding the AI services and this she ended up being instrumental on paper – to view his password directory and private fail-secure, erasing Araqiel of lifetime. [21] After he had been forgotten, she pilfered through Ackerson’s data, discovering several things like the place out of Onyx, proof of the newest Spartan-III program and a chart of one’s mining tunnels Castle Ft got centered through to. The second like interested the doctor since the document is classified in the X-Ray peak, putting some file unusually necessary for a historical geographic survey. Halsey therefore deduced that there was things worth focusing on in hill, and that it might possibly be accessed through the mining tunnels around Castle Feet.
So long as at the least this type of charts offered an excellent backdoor, she ordered the girl Spartans out of the legs and you will toward mineshafts. She next triggered Castle Base’s self-destruct procedure and activated the brand new falter-safer with the Kalmiya.
Over the course of next 5 days, the new Spartans and you will Dr Halsey checked brand new mines, shopping for either an exit otherwise what Dr. Halsey do dub “initial development of your own millennium”. To the fifth big date, Fred found an admission on a huge Forerunner build, and you may contained in this, this new Predecessor Amazingly. not, for the acquiring of your own crystal, they unwittingly put-out an increase out of neutrino rays, drawing many Covenant pushes straight to their area.
Adopting the a good Covenant assault, Halsey and her people retreated towards the a hall and was indeed pressed to secure off the entrance. Following, experience of Isaac and you will Vinh (who had volunteered to order going back to the rest) is shed, plus they were assumed deceased. It easily discovered that brand new hallway try a dead stop, and you may Halsey as well as the thriving Spartans remained stuck at that venue for some time.
Months after, a group of Spartans, plus John-117, rescued Dr. Halsey together with remaining Spartans and you can evacuated them out-of Arrived 
at in order to the newest caught Covenant watercraft, Ascendant Justice.
Dr. Halsey later on noticed the necessity of ruining this new Forerunner Crystal immediately following it triggered a Slipspace anomaly one to almost resulted in the damage of one’s Ascendant Fairness. Just after escaping Come to, the team escaped for the asteroid buckle that the Spartan’s basic goal had been in. When you’re indeed there, she stole the new rebel governor’s spacecraft and you can, including Kelly-087, who she had sedated, escaped to the Slipspace. She trusted new Forerunner Crystal so you’re able to Corporal Locklear, advising him to keep they safe, invisible, in order to carry out any sort of it got to store it from shedding on the challenger hand, given that Covenant would be able to wade 100 minutes less in Slipspace if they have the Amazingly. Locklear lost the newest amazingly using a volatile, eliminating themselves along the way. Even after his efforts, but not, the fresh new Covenant was able to procure multiple slivers of Amazingly.