I absolutely adore Mass Effect 3. I wanted a game that showed Reapers being the ****ing universe destroying machines they were...and the game showed that in spades.
Seeing a Reaper in the background just obliterating a planet was just cool and really sold the entire series and the reason why you were doing what you were doing. For instance, the dragon in Dragon Age Origins was neat but I never felt the story was in a dire place.
Reapers in Mass Effect 3? Yeah.....they are going murder everybody and how the **** am I suppose to beat them.