I didn't play ODST. Halo 1 is a masterpiece IMO, the best shooter of all time. Perfect. Halo Reach had the 2nd best story IMO. It was very emotional and I loved the build up to the Halo 1 story. Halo 3 was really good, nothing more to say. Halo 2 was too dark and the gameplay changes were very meh and the weapons as well. Halo 4 was just not epic enough. no halo theme song, the plot was not great, it was short, the new enemies were annoying, etc. but again just my opinion.