Holy crap, I exceeded the post count (50,000 characters). 0_0;
Since I can't place this in my first post, I'll need to place it here.
Dr. Catherine Elizabeth HalseySpoiler
Name: Dr. Catherine Elizabeth Halsey
Game: Halo
Appearance: Spoiler

Age: 68
Height: 170.2 centimeters (5 ft 7.0 in)
Weight: 53 kilograms (120 lb)
Abilities/Skills: Human Scientist/Inventor. Created the SPARTAN-II Program, the MJOLNIR Powered Assault Armor, Cortana, and many, many other things. Considered one of the most intelligent women of the 26th century.
Weapons: M6 Sidearm (Unknown model).
Weaknesses: Catherine Halsey is a human, meaning that she can be killed by anything that would kill a normal human.
Personality: Spoiler
“If people would just share things with me, I could solve all the world's problems.”
—Dr. Catherine Halsey
Little is given in the terms of social activities or even a list of friends. Her intelligence is unquestionable as well as the loyalty and respect she receives from the majority of her comrades and her Spartans. However, as seen in Halo: First Strike, her judgment is not always correct, although bearing the guilt of the Spartan program, her sense of right and wrong has differed greatly. It is obvious that she truly cares about her Spartans. She has a notable fondness for classical music, especially Debussy, and often asks nearby AIs to play select pieces as she works.
What can be gleaned is that she preferred the company of AIs, and, although she may be angered easily at being mentally defeated, always appreciates the simplicity of them. None more than Cortana, who was actually created from a flash clone of her own brain. She is well-versed in Greek mythology.
Guilt
Dr. Halsey carried extraordinary guilt because of the SPARTAN-II project, feeling that she had exploited the children and destroyed their lives, a feeling which was later passed to Cortana. Though she continued to support the Spartans and gained monumental prestige for her efforts, she also felt responsible for each one who died. She never could quite justify their exploitation as a "necessary sacrifice." She also had considerable respect for the Spartans, and addressed them by their first names (even with their armor on), which seemed to greatly annoy them.
Her feelings of guilt were made evident by the fact that she often referred mentally to "sacrificing the few to save the many," though this rarely worked to soothe her conscience. By the time she was rescued from Reach by the Ascendant Justice, she simply wanted to save as many lives as she could, believing that the war was not one that the UNSC could possibly win. While she knew that her own Spartans, the SPARTAN-IIs, couldn't be persuaded to turn from the war, she believed the SPARTAN-IIIs may not yet have been fully determined to win the war, and she set out to try and weaken their resolve to fight. When she was arrested Halsey allowed herself to be taken without any resistance due to her guilt.
Halo 4's prologue reveals that although Dr. Halsey carries the guilt of the SPARTAN-II project, she also sees them as the "next step" in the destiny of the human race.
John-117
“Do not underestimate them. But most of all, do not underestimate... him.”
—Dr. Catherine Halsey defending her SPARTAN's with special focus on John-117
Halsey also had somewhat of a unique relationship with John-117. Some of this may stem from him being the first subject she observed, but she had a great fondness for him and he was her favorite Spartan. Halsey told Cortana she considers him the luckiest and best of the Spartans and also apparently finds him attractive given her reaction to Cortana's comments on that. Halsey was responsible for John's first promotion to Squad Leader as a result of her acknowledging his leadership skills and suggesting it to Mendez. Halsey also had John's full trust and he always did his best to never undermine her authority.
Halsey decided to test her favorite SPARTAN's sense of ethics by handing over data concerning Avery Johnson and how his Boren's Syndrome made him immune to the Flood. She knew that if the data was handed over to ONI, Johnson would likely be killed and dissected in order to find a cure to the Flood infection. She estimated that there is a billion to one shot that they could have replicated Johnson's condition, but conversely ONI would do it to save Humanity from a greater foe. At first, John chose to sacrifice Johnson in order to try and save millions of people out of his duty to protect all of Humanity. However, John reconsidered and eventually destroyed the data due in part to the sacrifice of Vice Admiral Danforth Whitcomb and Lieutenant Elias Haverson, believing that one man could make a difference as opposed to sacrificing him for the greater good.
Bio: Despite being shocked that she arrived in the "real world", she at least had a rough idea how such a thing was possible. With no way to go home, Dr. Halsey thought it would be best to simply try and adjust to this world. Thanks to her reputation as one of the most intelligent women of the 26th century, along with her success in the SPARTAN-II Program and MJOLNIR, it was easy for her to get funding for her projects. Within a month, she had already founded Prometheus Labs, a research center and base of operations for the SPARTANs. After a couple months, she learned that Spartan-B312, otherwise known as Noble Six, survived Reach and was transported to the real world as well, and decided to invite him to stay at the Labs. Six accepted, and with his help, she began training a new breed of Spartans. The new Spartans were extraordinary people recruited from all around the world. Soon, word of Prometheus Labs's success, breakthroughs, and current research attracted even more scientists, volunteers for Spartan eligibility, and workers, accelerating the Labs's growth to dizzying heights, and at the helm of it all was Dr. Catherine Elizabeth Halsey. All of the scientists under her authority were a great boon to the Labs's progress, but none could solve the problems Dr. Halsey could. While in Prometheus Labs, Dr. Halsey also developed an experimental MJOLNIR armor system, a new breed a Spartan, the SPARTAN-Vs, and many other things.
In the past four months, Dr. Catherine Halsey has built up Prometheus Labs's defenses, greatly improved its security, and has helped a boy by the name of Chung develop a large Disfrozen Portal.
Traumas: Dr. Halsey bears an extraordinary amount of guilt over the SPARTAN-II Program. She feels guilt for kidnapping the children, destroying their lives, and putting them through the program. She feels guilty for condemning each of the children to a life of endless war, then a violent death in the very end. The guilt stretches s ofar that she tries to rationalize the SPARTAN-II Program by saying that she was "sacrificing the few to save the many", but it rarely ever works.