Halo 3 was three at one time: Campaign Complete: Legendary and Heroic, and also get over 15,000 points on Cortana. I spent one hour and 15 minutes doing Cortana, the last mission I needed to do to completle Legendary, on solo, which my friends told me was suicide since it took them ages to do on co-op, and only one of my friends did it solo before. It felt like I wasn't completing a game, it felt like I was going to throw a ring in a bloody volcano. For some reason I also put on four skulls, and I still don't know why I did. Was absolutely epic, though.