A must-have for all Xbox 360 owners!
Campaign: The story starts you off as Master Chief hurling downward to Earth in a forerunner spacecraft and resumes about where Halo 2 left off. There are nine missions to play (ten if you count the opening cutscene) and you are right in the middle of everything in each one. When you're not getting headshots on Grunts and sticking Brutes, you're fighting the Flood, and they're back meaner than ever. There are four difficulties to choose from: Easy, Normal, Heroic, and Legendary. Beating Halo 3 on Legendary may seem daunting at first but if you get a 4-player co-op session going, it's a piece of cake. Skulls make playing the campaign more challenging, but I'll leave it at that because I don't want to spoil anything.
Matchmaking: There are three types of playlists to choose from in Halo 3: Ranked, Social, and Hardcore. As you level up, you must achieve a highest skill in a ranked playlist, so expect the Ranked playlist to be very competitive. Social only tracks EXP so it is more laid back and fun. Hardcore consists of three playlists: MLG, Team Swat, and Team Snipers. MLG and Team Snipers are pretty straightforward and Team Swat starts you with a Battle Rifle and no shields, so aim for the head. The only problem I have with matchmaking (and Halo 3 in general) is that people make 1 month accounts just to wreck kids that are lower levels than them. So you will see Gunnery Sergeants and Lieutenants that are level 40 and above.
Custom Games: Best played with a group of friends. You can choose what game type and map you want to play on, and even make your own game types. You can also play on maps you created or downloaded. There are plenty of games to play in the Custom Games.
Forge: In a nutshell, Forge is where you can edit the default maps, or even create your own if you have the Foundry map and the Sandbox map (Heroic and Mythic map packs required). After you see all the items you get, you will soon realize that the options are basically endless. Just be aware of the budget and item counts.
Theater: In the Theater, you can watch previous matches from Campaign, Matchmaking, Custom Games, and Forge. You can also take screenshots and upload them to your file share and your bungie.net service record. Have a picture of yourself getting a Perfection medal in a Team Slayer match? Then take a screenshot and show the world! You can also take Film Clips to save a memorable moment that you want to share.
So after reviewing each of the main categories in Halo 3, I only found one noticeable problem, that being the infamous 1 monthers on Xbox Live. Other than that, I don't see any huge problems. The weapons are pretty balanced, you can customize your guy for online play, and the campaign is about right. If you have an Xbox 360, I highly suggest buying this game. It's worth it.