Cortana is Weapon from the Games
She used the artifact to send herself to the past to fight the Endless, but the Endless had already sent the Blessed One to fight this temporal intrusion.Any other differences in timeline can be explained by groups trying to alter the timeline or protect it.
We'll see some Arc Welding of Halo 1 and 2
What the title says. Once the series gets around to the battle for the first Halo, the threat of the Flood will spur John and either Makee, the Arbiter (assuming he's a character), or both to temporarily set fight together for the sake of survival, with the latter having their faith shaken by revelations about Halo's purpose. The truce will break down once John decides to outright destroy Halo, but it will nonetheless plant the seeds for the Covenant Civil War.John's parents were researching the Forerunner artifact on Eridanus
It's entirely too much of a coincidence for John to "just happen" to have found both artifacts entirely by coincidence. More likely the "terraforming experiment" story is a cover, and his parents were really working with Halsey to find out more about the Forerunners. Considering how disturbed John's drawings made his father, they probably found out the artifact led to weapons capable of wiping out all life in the universe, and decided the safest thing would be to hide the truth from Halsey. But she found out- including the fact that the artifact gave John visions- so she kidnapped him, killed everyone from his colony to cover her tracks, and made him a Spartan in the hopes he would lead her to the missing artifact.Squirrel will become The Starscream in season 2.
He wanted to put his drunken rant against Soren behind him. But when Soren crushed his foot, Squirrel takes it personally and plans to get revenge by overthrowing Soren. He might even team-up with Hasley.If Arbiter ever appears on the show, he'll be reprised by Keith David like with Cortana.
