Honestly the only Halo games that are anything special are 1, 2, and Reach
I didn't think 1 was even that good. Think of what you know from the game alone, not the sequels or supplemental media.
The ring is made by the Forerunners. Okay, who are they? Do the main characters know who this is? Have they discovered other forerunner constructs prior to this?
Encountering the Flood. Does this mean anything to the characters or is this the first time fighting them?
343 Guilty Spark mentions a previous conversation apparently mistaking Master Chief for someone else. Who?
The Flood can't killed or contained, thus the need to destroy their food source and hope that... I'm not really sure, were they expected to die out naturally or just hold a static population while someone figures out how to properly kill them? Except the game mechanics have them fall to conventional weapons just fine and plot wise they were contained for however long before the Covenant interfered. Are they even that prevalent in the galaxy?
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No locked doors, no windows barred. No more things to make my brain seem SKARD. Look at Mr. Technical over here >.> -BTB