Nine years. That’s how long ago the first Halo hit Xbox and since then, the sci-fi series has proven to be Microsoft’s (MSFT) most enduring game franchise and a paragon for the first-person shooter genre. All told, the company has sold 34 million Halo games worldwide and posted $1.9 billion in Halo games and Halo-related merchandise sales.

The latest, Halo: Reach, is a bittersweet send-off for Bungie, the software development team behind the series. It’s the last Halo title from the team before it starts work on a new game property as part of its new 10-year deal with Activision. Presumably, an internal team at Microsoft will take the reins and develop future Halo games, but Reach takes the franchise full circle and answers all the questions fans have wanted answered.

Reach takes place in 2552, after the fall of the human-colonized planet of the same name and before the events in the first Halo. The campaign follows the adventures of Noble Team, a six-person special ops squad caught in the intergalactic war against the Covenant, a theocratic military alliance of alien races who have it out for humans. Instead of playing as franchise mainstay Master Chief, players take control Noble Six, a mostly-silent everyman or everywoman-type — you can choose the gender on start-up — who joins just as Noble Team sets off  to investigate what happened at a downed communication outpost.

Campaign mode will take 10-plus hours to finish, depending on the difficulty level and how quick you are with any one of the new weapons at your disposal, from the long-range Designated Marksman Rifle (DMR) which takes out pesky enemies in one shot, to the Needler Rifle a slower, more accurate version of the popular Covenant staple that shoots deadly translucent pink splinters. Like the DMR, it can pull double-duty, performing long-range and executioner-style shots, but on top of that, if you bury enough shards in the enemy, and he’ll blow up, cursing you as he goes. The last is obviously unnecessary, but it adds another layer of fun to the proceedings.

Initially, the world of Reach feels very much open-ended, but it’s much more focused than the universe presented in Halo 3. Whereas that game had New Mombasa as a centralized world, Reach keeps pushing forward with sprawling new vistas: lush green countrysides, grim industrial sites with intricate beams and platforms, and claustrophobic hallways in the depths of space. During one level, the Noble Team flies above the city of New Alexandria and lands from building to building to deal with separate threats. It’s fast-paced and heavily-scripted, but the adrenaline rush is unavoidable. It also shows off the game’s eye-popping proprietary graphics engine, which handles thousands of detailed objects onscreen with nary a stutter.

Lone wolfs would be content with the single-player mode in Campaign, but for players craving some quality multiplayer action, Bungie does not disappoint in that department either. First off, Campaign mode can also be played cooperatively with up to three other players, either in side-by-side split screen or online, and the challenging Artificial Intelligence — which becomes damned near impossible at the “Heroic” difficulty level — ramps up accordingly. The Firefight mode still pits anywhere between one and four players against computer-controlled Covenant enemies who come in almost endless waves, but this time around, players can connect to Xbox Live and find partners themselves rather than leave partnering to chance. The match’s host can also set a time limit and customize any number of options, including number of rounds until the end of the game and “loadouts,” or equipment sets. There’s also the Forge World, an intuitive map editor that pretty much lets you build your dream Halo environment.

After more than 20 hours with Reach, it’s fair to say that what Bungie has accomplished with the game is no small feat: incredible graphics, engrossing gameplay that oftentimes has you total immersed, and tons of single-player and multiplayer options that will keep players busy for hundreds of hours if they’re so inclined. If there’s a weakness to nitpick, it’s that the new points-based system in the game, built up throughout the various modes, doesn’t go far enough: it’s great to use all those points to customize Noble Six’s armor until s/he resembles a stormtrooper on steroids, but ultimately, the changes are superficial. Why not offer increased ammo options or a larger health gauge?

In the end though, Halo: Reach is a fitting farewell — and a veritable love letter — from the company to tens of millions of players. Maybe it’s best if Microsoft let the franchise end with Reach, because it’s hard to imagine where to go from here.

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