- last post: 01.01.0001 12:00 AM PDT
well here's my take on it:
we know that this cutscene probably won't be in the actual game. We know this because Frankie talked about how they didn't take too much time away from development in creating this annoucement trailer. But, I think we can assume that the event depicted will take place.
What we know is this: The ark will be activated a third of the way through the game. This is significant. We don't necessarily know that we saw the ark being activated, but I believe that is what we saw, with the main evidence being that the MC and the Covenant were acting with a sense of inevitability. The Covies weren't stopping to kill the demon, they were gathering for the great journey.
OR
We could take the "event" to mean a vision/transmission that Cortana is having or sending to the MC. That would mean that the big explosion we saw won't happen a third of the way through the game, but the transmission depicting it will...
my guesses:
if it is the actual activation of the ark that will happen 1/3 of the way through the game, then the ark will not destroy everything (obviously), but instead act as a gateway through galaxies or time and bring back the forerunners, who will destroy lots of things...
if it is the transmission that happens 1/3 fo the way through the game (more likely imo), then Cortana and the Gravemind have joined, in some sense. It is likely that the Gravemind has assimilated Cortana or is controlling her, though to what end we do not know. We do not know if Cortana is allowing herself to be controlled in an attempt to help save humanity and help the MC, if she is just corrupt and evil, or whether or not she is rampant. The Cortana Letters would suggest that she will be rampant by the end of the series. My guess is that the Gravemind and Cortana are using each other in an attempt to get to Earth to further their own devices and stop the Ark from being activated, both in search of self-preservation...the Gravemind for the flood, and Cortana for herself...(AI lasts only 7 years, and I think she has gone rampant and is acting to save herself, not humanity, which will cause a pseudo-betrayl by the end of things...she won't be completely good or evil, and the player will not know whether or not to trust her...)