Remastering and remaking a treasured video game like Halo: Combat Evolved is not a fair task for any developer to be assigned. No matter what, there are going to be changes (or non-changes) that fans of the original game aren't going to like -- so the real trick is, can you balance enough new and old content to satisfy both crowds? Looking at Halo: Combat Evolved Anniversary, 343 Industries found a very elegant solution.
Playing through Halo with new graphics and musical arrangements from Skywalker Sound really tugs on those feelings of nostalgia -- and the first time you press the back button, you'll be taken aback by the visual upgrade. Seeing every part of Master Chief's first adventure in high-definition splendour is a beautiful thing, especially when you see and hear the new elements that accompany the original game's source code. It arguably sets a standard that most other re-releases should follow, rather than just lazily porting older generation games to new HD systems.
Personally, I don't recommend reliving Halo alone, since playing it on co-op through Xbox Live really gives you a better appreciation for the game on higher difficulties. Moreover, it also helps make up for the lacking level design. Many of those mid-level stretches when you're just running to the next combat point (or God forbid, you let computer-controlled allies drive you there) are more enjoyable when you're running-and-gunning alongside someone who actually knows what they're doing.
However, even with all the extra polish, Halo: CE Anniversary stumbles in a few areas that are harder to overlook. Graphics-swapping, the game's most touted feature, feels much more sluggish than it was in early presentations at E3 this year. So much so that you'll need to remove yourself from combat to do so without getting shot during the black loading screen.
Moreover, not being able to swap graphics engines during cutscenes is odd. For veteran players, you'll know when to make the switch, but new (or more forgetful) players will likely miss it the first time around. If there's a lot of action happening on-screen (re: most explosions), you will notice the occasional hiccup in frame rate, a slight screen tear, or even an enemy Elite that slumps right through a wall and tumbles out of sight. It doesn't happen often, but as 343 Industries said, all the original code from the first game is in there. Even the blemishes, apparently.
Still, such things aren't seen often in the multiplayer at all, which is the real meat of Halo: Combat Evolved Anniversary. In fact, it's nice that people who don't buy the game still have the latitude to buy the maps -- revisiting old haunts like Beaver Creek and Hang 'Em High is a lot of fun, and the tweaks made to each map actually force you to revise your tactics. Old camping spots won't be as secure and chokepoints are different, but some old strategies still work just fine. It's not the level layout that's really changed, just how quickly you can manoeuvre from one area to another.
But while the modern trimmings that you get with multiplayer really make the game work, Firefight still leaves a bit to be desired. Ally A.I. isn't much help when the game starts throwing bigger enemies and bosses at you, and while the Installation 04 battleground is fun, it would've been nice to have more areas to explore. It's inevitably going to be compared to Horde Mode from Gears of War 3, but the comparison is outright unfair. Firefight is more a perk than a dedicated mode, and Halo's never had an advanced cover system, anyway. So, you're really just spending the entire time setting up crossfire traps and circle-strafing around your base (or, using a jetpack).