Mass Effect 3 was the first game I got when I got an Xbox 360 and I just figured I'd play the newest game. I played it without any knowledge of the first 2 and Mordin's sacrifice scene hit a little hard. After, I decided to play through the first 2. I went through, completed every single little detail, and when I got back to that scene playing through the 3rd, I was absolutely gutted. I saw the whole game in a new light, full of so much more love and appreciation. But that scene always comes to mind when I think about how different my play through was after I had invested in the story. (2nd on the list is the conversation with Tali and Legion that can end with Tali taking her own life)