Developed exclusively for Xbox 360 by acclaimed developer Bungie, “Halo 3: ODST” is a new game in the “Halo” saga that lets people experience events leading up to the epic story told in “Halo 3” through the eyes of an ODST (Orbital Drop Shock Trooper), as they search for clues leading to the whereabouts of their scattered squad and the motivations behind the Covenant's invasion of New Mombasa.

“…a superb addition to the franchise and a must-play for anyone who craves top-notch action.” 9/10 – Gamespot
“…when it comes right down to it, every Halo fan should buy this game.” 9/10 – IGN

Halo 3: ODST also introduces Firefight, a new cooperative multiplayer mode where up to four players can assume the role of an ODST squad and fight together to take on increasingly challenging waves of enemies.

Also included are three new “Halo 3” multiplayer maps on a 2nd standalone disc, which includes all original “Halo 3” maps, as well as the “Legendary,” “Heroic,” and “Mythic” Map packs for a total of 24 maps.

Review by Gamespot

“…Halo 3: ODST is an excellent package. The delicate construction of the story adds a new wrinkle to the typical Halo plot, and the action-packed campaign levels are full of intense battles and surprising encounters. Firefight mode is a standout addition, crafting highly addictive cooperative battles for players to experience. It's disappointing that the competitive multiplayer hasn't received any updates or innovations from its Halo 3 incarnation, but it's as fun as it ever was, and well worth sinking more hours into if you haven't yet seen the many downloadable maps. ODST is a superb addition to the franchise and a must-play for anyone who craves top-notch action.” 9/10

THE GOOD – Firefight mode is a blast, Campaign is well-paced, with tons of great moments, The between level sections are moody and engaging, Same great multiplayer from Halo 3, with three new maps, No Flood.
THE BAD – Multiplayer is mostly recycled from Halo 3, Damage indicators are annoying.

Review by IGN

“…There are places where Halo 3: ODST could be improved, but when it comes right down to it, every Halo fan should buy this game. Even if you've lost interest in the franchise over the years or haven't ever given a Halo game a look, you'd do well to grab ODST and a few friends for some of the best multiplayer gaming around, especially with as wonderful an addition as Firefight. The campaign is a tad short, but well-crafted and exciting. Then there's a whole disc full of multiplayer maps, though you may already own the bulk of them.
Halo 3: ODST isn't a true sequel, but it is more than a standard expansion. If you're on the fence about buying it, drop your reservations and go snag a copy. If you love Halo, you owe it to yourself to pick this up as soon as you can.” 9/10

IGN RATINGS FOR HALO 3: ODST (X360)
9.0 Presentation
A tight story and well-crafted world make for one of Bungie's best efforts to date.
9.0 Graphics
The Halo 3 engine is starting to show its age, but the art team has done its best to make this one a looker.
10 Sound
Another Halo game, another fantastic soundtrack.
9.0 Gameplay
The campaign might be a tad short, but it sure is satisfying. The fresh approach to Halo is a winner.
9.0 Lasting Appeal
Firefight is awesome. It would be even better with matchmaking.
9.0
OVERALL
Amazing
(out of 10)

Features:

• All-new campaign content. The “Halo 3: ODST” campaign explores mysterious events leading up to the Master Chief's return to New Mombasa in “Halo 3.” Experience the fate of Earth from the brand-new perspective of a special forces ODST (Orbital Drop Shock Trooper), adding a unique outlook and new gameplay elements to the events that unfold in the trilogy's finale. This new chapter captures the same great feel of previous “Halo” experiences while offering fans new tactics, tools and weapons to defeat the Covenant.
• A new hero: Prepare to drop. ODSTs or “Orbital Drop Shock Troopers” are highly-trained special forces operators. Known for their courage, valor and willingness to tackle missions no sane soldier would, ODSTs pride themselves on being the first unit deployed into hostile situations, often in one-man drop-pods that burn through planetary atmospheres at break-neck speed.
• Expanded multiplayer experience. No “Halo” game would be complete without groundbreaking multiplayer content. “Halo 3: ODST” introduces an entirely new way to play “Halo” with Firefight, a cooperative multiplayer mode included on the campaign disc that lets up to four people jump immediately into combat. As an ODST squad, you will face increasingly challenging waves of enemies together, striving to earn the highest scores possible, while various “Halo 3” “Skulls” are progressively activated. The experience is intense and ever-evolving. “Halo 3: ODST” also includes a separate, standalone multiplayer disc which includes three new “Halo 3” multiplayer maps, all original “Halo 3” maps, as well as the “Legendary,” “Heroic,” and “Mythic” Map packs for a total of 24 maps.
• Ever-growing community options. Players will continue to enjoy all the great “Halo 3” technological innovations, including Saved Films, screenshots, Campaign Scoring and four-player co-op over Xbox LIVE. All of the new “Halo 3” multiplayer maps fully support the Forge editor, offering near endless gameplay customization possibilities for fans.