I just finished ODST's main story mode. It was actually pretty enjoyable, and far moreso than Halo 3's single player was, which in retrospect is pretty bland. The entire ordeal took me about four hours.

I'm going to assume that you're already familiar with this game and it's basic premise. If not, please see here.

You play as The Rookie for the majority of the game. During his adventure through the ruins of New Mombasa, Kenya. I don't think I've ever played a game set in Africa before, and I certainly haven't played one set in a futuristic Africa. The majority of the city is typical futuristic urban fare; tall skyscrapers, futuristic looking cars and panels. Withing the city there is a giant wildlife reservation, complete with safari trails and rest stops. The level design and art direction is all amazingly high quality. There is significant and interesting detail throughout the city, from the flashing panels displaying warnings and advertisements from the ruined cars and dead soldiers. It actually reminded me of playing Fallout 3, but in the Haloverse at times, due to the sense of being the only person left in a once populated but now destroyed environment. More so even, as I played most of Fallout 3 in sneak mode, trying not to get raped by deathclaws. Replace deathclaw with Brute and you have the ODST experience.

Not really, seeing as even though technically the Rookie and all of the other playable ODST's are human, they can take a lot of punishment. You honestly have very similar health to a Spartan, just now when you take damage, it becomes a lot harder to function as your screen with become more and more red. Lots of red. The health system is very much like Halo 1's. Where as, you have a shield that regenerates, but your health under that shield doesn't. In ODST, you can recover lost health using Opicans, which are just a fancy way of saying healthpack.

By the time you're done playing the pretty short campaign, you will have been pretty much everywhere over the city and the parts directly surrounding it as all of the ODST Squad (Rookie, Buck, Romeo, Dutch, Mickey). And I actually started to care about each character's fate nearing the end of the whole ordeal. When you first meet each of them, they are presented in a stupid, not well thought out way that tries to contrast THE WORLD ENDING HOLY SHIT with "lol this is a good time for slapstick". There is also a love story that plays out and actually leads up to a (SPOILERS) kiss around the end. It's weird because the halo series have been oddly lacking in real humanity, and this is the first time in a halo game where I actually cared about the characters.

Multiplayer.

ODST's campaign is fully playable with four people, but I haven't got around to playing it that much.

Most of my focus has been on the new multiplayer gametype: firefight. Firefight can be summed up as Gears Of War's Horde Mode meets L4D's survival mode plus Halo and minus pills with slightly different scary aliens that want to harm you and your body. It's considerably easier than Survival Mode, but that's not saying much (most survival mode games don't last more than 4 minutes before everyone is killed). This isn't to say it's not challenging, as it certainly gets very intense later on.

For the uninitiated, Horde, Survival, and Firefight are all endless wave gametypes. It's almost a throwback to a time when games didn't have any endings, and the only objective was to get a high score. Enemies will never stop coming, and you will only be permitted short breaks between waves. You will have to manage health and lives, but you will also have to deal with skulls that come into play at the start of every round. These skulls augment the game in different ways, such as making enemies more inclined to avoid danger or to cause all of the enemies to wildly throw grenades. The difficulty really picks up with skulls that augment your health come into play, such as the Black Eye skull, which will cause your shields not to regenerate normally; you can only get them back if you melee an enemy.

There are several different maps to play on, each very different from the next. Some are wide open and are very accessible to vehicles while some are very closed in and are filled with close quarters fighting.

With four people, it's just fun. Probably not as fun as L4D but I'm likely just biased and that's not a fair comparison at all. They are vastly different games. (Okay so Hunters from Halo are similar to Tanks from l4d, especially in survival/firefight, fuck you) Having four ODSTs fending off against hundreds of brutes and actually winning ( for a short time at least ) is extremely satisfying. Having team tactics actually result in a difficult wave ending sooner is a delicious feeling that rivals any similar co-op experience you can find online these days.

Also, along with the first disc of ODST, there is a second disc that functions as a complete Halo 3 multiplayer disc. By complete, I mean all of the maps from the map packs are already installed on the disc itself. You don't need Halo 3 for the disc to work, although if you do, all of your settings will carry over automatically. It includes 3 exclusive maps as well.