I have written in the past about how I am a massive supporter of Mass Effect 3. I enjoy the ending of that game a whole bunch and I think it says some interesting things about fate, inevitability and cycles. So perhaps, there is a bit of bias about this trailer, but I think it is a great advert for the game. Much of Mass Effect 3's marketting campaign was about telling the smaller stories of loss due to the Reaper invasion. These are stories the main game would have struggled to get into with out feeling forced. Besides, Commander Sheppard should be flying around the galaxy taking the fight to the Reapers directly. What is nice about the marketing campaign was that it helped reinforce these sadder stories of loss that the main game wasn't going to focus on. That is another smart use of a cinematic. Lots of people complain when they essentially see the main characters fighting a massive battle they would like to play through. So focusing on sections of the mythology that the game won't get to focus on helps to expand our knowledge of what is going on in this universe. Also, the image of a massive Reaper lowering down towards a little girl is rather haunting.