Marathon: Durandal is a great remake of the original, also including extra modes that are well worth the 800 points.

User Rating: 9 | Marathon: Durandal X360
Marathon: Durandal is a great game, and if you can stomach the supposed sea-sickness and dated graphical style, you are in for a great time. If you bought DOOM, then this is the next step, a great purchase in the old-school shooter category. The Singleplayer mode can be confusing, but nothing too difficult that GameFaqs couldn't solve easily. The multiplayer modes are a blast, but due to a small online community, they are most likely to be enjoyed by friends in splitscreen. An awesome addition to the game is a survival mode, which starts one off with an amazing amount of firepower to pick up, and throws the galaxy's worst at you. While an Interesting Lesson in the origins of Halo, it still stands out on its own as an XBLA title.