- last post: 01.01.0001 12:00 AM PDT
Sword. Master Chief is indeed a formiddable weapon by himself, however, without Cortana he would have died on numerous occasions. The books show that time and time again. She also is his protector, she is a tool. She is both a shield, in that she protects the Master Chief from evil, she is a sword in that she can also destroy and eliminate targets, digital or otherwise. Cortana is a tool, a sentient one, but a tool none-the-less. I believe that she has been corrupted by the gravemind , and has discarded extra "unnecessary protocols" in her system. Or they were corrupted. This would leave her with the basic and rudementary functions that would allude to why she is speaking this way. Obviously she has either destroyed or escaped the gravemind, i.e. the "defience of demons and gods", and had to remove some of her programming to survive. She learned some things from the gravemind, "I know you, your past, your future..." During this time she probably also learned about the truth behind the forerunner and now sees herself as a tool to save both the human race and the master chief. Making her a Shield to protect him from destruction and a Sword to destroy the threat.
I know it was hashed together really quick but that is what I am geeting from the movie clip and the backstory.