Okay, this is definitely entering the semantics danger space. I totally agree that the idea behind [spoiler]this crazy magical space device being the only hope for the galaxy even though we don't know why is dumb.[/spoiler] I'm willing to let it go because the story of the first game was you were the only person who believed the evil alien overlords that want to wipe out all life (again) basically solely because of a weird dream and the guy actively trying to make you look disreputable admits it to you. I mean obviously it worked out but clearly gathering all the details isn't a big requirement of Shepard's.
Deus Ex Machina though? I don't think so. I mean it certainly fits a literal definition, but I wouldn't hold it to the cop-out connotation of the term that you seem to be. I mean, the entire game you have to [spoiler]finish the crucible, find the catalyst, beat the reapers. When you learn the catalyst is the citadel and the reapers move it the plan gets fleshed out a bit more. New plan: Shepard opens the citadel, the crucible gets hooked up and Shepard activates it. All of that happens. Nothing comes along and changes everything, we're simply given a bit of the what and how (which we agree there could be more of still) and then go about our business.[/spoiler]
Completely seriously I'm curious if this ending would be more or less Deus Ex-y to people
[spoiler] You get the catalyst from Cerberus, it resembles a simple Prothean orb. Returning to the crucible everything is hooked up and Shepard tries to use it, having another vision shot into his head as the Prothean beacons and cipher had. It becomes clear that destroying the Reapers wasn't the original intention of the device, and that you could instead control them. Also, if you were able to gather X amount of war assets, the crucible's design was so perfect it unlocked the potential to merge all organic and synthetic life. All ending cinematics remain the same.[/spoiler]
