Reach. Halo 3 was better storywise in my opinion (I'm just a softie for the Chief, I guess) but I really enjoyed the multiplayer mechanics of Reach far more. From how much they expanded on the armor system, which I think is better than 4 or 5 again my opinion, to having more gamemodes and other stuff. Too much to go into in a small post like this, but I just wanna stress it was the most fun I had in custom games/forge/online matchmaking I ever had in any halo game, ever.
I honestly wish Reach itself would get a reboot for the PC or even to the Xbox again, I just loved it so much.
most people probably might not like how they made it all gritty and realistic from just a space shooter but I still enjoyed it and thought it was enjoyable even if I was just screwing around in forge singleplayer.
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