Halo 2 - one of the greatest games on the X-Box (the first X-box, mind you).
After the destruction of Installation 04 or as some others know it, Alpha Halo, both the Covenant, UNSC Humans and the Forerunners have moved on. The Covenant have recruited two new speices, known as Drones and Brutes. Both are equally annoying. The Forerunners have a new type of Sentinel, the Sentinel Major that shoots out blue beams. The Forerunners have also constructed an Enforcer, which is quite impossible to destroy if wrong weapons are used, but simple when you have the right tools. The UNSC Humans have better equipment, however, downgraded some, and have somehow, improved the strength of the Marines slightly. Well, here goes...
Halo 2 has improved from its predecessor, Halo: Combat Evolved, with some advantages and some disadvantages. Let us begin with the advantages. Wielding two weapons at once is allowed, so long as they are permitted. This is called dual-wielding, and dual-wielding can only be done with single-handed used weapons. Also, you have the ability to play as The Arbiter, an Elite which failed to protect the Halo, Installation 04 aka Alpha Halo. Again, please remember to play Halo: Combat Evolved before you played Halo 2. Personally, I think that the Arbiter is better than the Master Chief because the Arbiter has stronger allies which are capable of wielding Energy Swords unlike Master Chief's Marines. The Arbiter also has access to Active Camoflauge, which makes him invisible for five seconds, and is much more useful than Master Chief's now useless torch-lamp sort of thing. Another advantage is that players can now access the Covenant Wraith. Remember those vehicles that shot blue mortars back from Halo: Combat Evolved? Now, you can access them. There is also a new type of Warthog, known as the Gauss. It shoots bursts fo gas, and is more useful than that old Warthog back in Halo: Combat Evolved. Continuing with the advantages. You also have the ability to hijack vehicles and destroy them (including Warthogs), making the game even more realistic. There are also new weapons, for example, the Fuel Rod Gun (remember what the Hunters shot out on Halo: Combat Evolved?) and the majority-of-a-time-useless Sentinel Beam. The rocket Launcher has a lock-on ability, however, some might consider that an disadvantage. These are just a few advantages. Now, onto the disadvantages. As I said before, the Master Chief's Marines and Lamp-Torch thing is useless. There are far more glitches on Halo 2 than Halo: Combat Evolved, however, this could be an advantage for glitch-lovers. The Assault Rifle is replaced by a craptacular SMG, and the M6C Pistol is replaced by the ever-crappy M6D Magnum. Overshields cannot be found on Campaign, neither can Active Camoflauge (but who needs Active camoflauge when you've got The Arbiter?)
The graphics of Halo 2 are great, and as you can imagine, even better on an X-Box 360. They can be seen clearly and have upgraded from Halo: Combat Evolved. Not much I can say here, but except that it has been improved. The audio is excellent, and so are one or two songs from the Halo 2 Soundtrack (yes, H2 has a soundtrack). If you swing your Energy Sword, or destroy a Warthog, it sounds realistic. Even the talking, however, i certainly hate it how Master Chief dors not talk much. I won't tell the story - it ruins how you're gonna play. Overall, Halo 2 is a great game, and should be pretty cheap these days (I saw one at EB Games for $19.95). Get it, finish it, then play Halo 3.