User blog comment:The Milkman/Madness and Genius/@comment-2076032-20121209105806/@comment-2250460-20121209183701

My point is that you don't have to play the full game (although you should) to understand.

All you would really need is maybe the Leviathan's Revelation and that's all. Everything else present in ME3 (aside from maybe the Thessia VI) that foreshadows the endings has already been foreshadowed in the first two games.