It was a brave move to move the Halo franchise away from Master Chief's point of view. After the success of ODST, Bungie continued this move with a prequel to the original game and how Cortana was discovered. You play as a ragtag team of elite soldiers and you play as Noble Six. The funny thing about Noble Six is that he is basically a nobody, and you witness the deaths and heroisms of your fellow squad mates and search for the last hope of humanity.
The game plays and feels exactly like Halo 3 which is a good thing. The game has many of the same weapons and power-ups as Halo 3 as well. The game has a decent length of 9 levels and the progression is well done. Each level takes place in a new area so I never felt bored like I did in ODST. From outdoor areas with sweeping vistas to tight and controller corridors. The game is fast paced, hectic, and a lot of fun. I felt it was less difficult than previous games and much more balanced. I was able to quickly get a feel for my favorite weapons and the ebb and flow of the gunplay and enemies.
Again, the same enemies in Halo 3 exist here with the introduction of the Brutes from Halo 3, they make for a formidable foe and some of the toughest in the game. There are a few flying creatures, and I found there was less vehicle combat in this game than any others in the series. Most of the game is on foot and there's nothing wrong with that. Most objectives will require you to activate or defend something and this is typical for FPS games back in the day, but it never felt old. Halo has this magical formula of great AI, enemy balance, and knowing when and where to use each weapon. You know what situations calls for which weapons and when you see the weapon you go for it, and when the situation flips you know when to drop it and go for another. I know in tight corridors I want a shotgun so I drop the pistol and pick up an energy rifle as a scoped weapon is useless. When I run out of ammo I know there is an alien equivalent lying around which is great.
Reach just really isn't much different than Halo 3 or any game before or after it. It's a solid game with one of the better campaigns in the series, and the multiplayer is rock solid. With this being a spin-off you're expected to see asset flips and familiar gameplay, but shift from Master Chief is what makes it feel a little fresh. With the update for The Master Chief Collection, the game has better visuals, runs at 60+ FPS, and supports ultrawide screens, mice, keyboards, and current generation hardware. It looks dated, but clean and feels like a modern shooter does on PC. I didn't run into any crashes or major glitches so its a solid port.
I don't have much else to say other than it's a good Halo game. The ending is solid, albeit sad, and sets you up for the main trilogy. I loved Halo 3 so being able to get back into that era of Halo was great, and the upgrades make this a no-brainer for any Halo or FPS fan. If you don't like Halo this game will not change your mind at all as it's about a rudimentary for the series as it gets, and the story is a little on the light side compared to other games in the series. I didn't care for any of the characters, and if you aren't familiar with the future timeline it won't make much sense to you.