erezike wrote...
- there is also the part where anderson say if shepard wasnt on an off grid mission doing god knows what god knows where.(shepard never went off grid for more than a few hours in mass effect 2)
I know this is only a minor thing, but I disagree. Shepard was off the grid for most of ME2 - he only ever checked in when you visited the Citadel, and unless you did that every other mission, then "Away, working with a terrorist organisation" is legitimately off the grid.
Anyway, let's get into timeline stuff:
Retribution has to take place after the Suicide Mission. TIM directly references getting tech from the Collector Base (although it's ambiguous over whether or not the base was blown up). Judging by Anderson
not referencing Shepard having been arrested, but instead simply being off the grid, this is before Shepard has been taken in by the Alliance.
Therefore Retribution takes place during the ME2 endgame. (Which I consider to be all of the time between the Suicide Mission and Shepard being grounded by the Alliance.) During the ME2 endgame, stuff on the Citadel and Omega are unchanging compared to how they were just before the Suicide Mission.
ME2's endgame doesn't really have plot content - it's just there for you to finish up any remaining missions. So it wouldn't recognise stuff like Grayson tearing through Omega, or Cerberus being attacked. Those things simply aren't in game - presumably because Retribution was written after ME2 was released.
Arrival can take place anytime between Horizon and ME2's endgame. It's entirely up to the player. For the purposes of the Vega-Omega comic, however, Arrival takes place 3 days before Shepard is grounded. This will be non-canon for anyone that didn't do Arrival as the very last thing in ME2. (Since the comic is only a few pages long, I think you're being picky if that bothers you. Dragon Age has done entire books that will be non-canon for some players.)
Which just leaves Anderson's comment within Retribution that Shepard is off-the-grid. As I've said, Retribution is post-Suicide-Mission, and one of TIM's scenes implies Shepard is no longer with Cerberus, so where is Shepard? What is this off-the-grid mission?
Does it matter?
Depending on your playthrough, it could be anything from LotSB, Overlord, spare Loyalty Missions, Arrival, or just getting drunk on Illium. Presumably it was left ambiguous because they hadn't yet decided how they were going to join ME2 to ME3. Karpyshyn needed a non-specific reason for Shepard to be unavailable. Off-the-grid just means "Whatever you had Shepard doing during the ME2 endgame."