Yeah, halo 3's campaign is pretty short, but I'd argue you can't actually consider halos 2 and 3 as separate games when evaluating their single player campaigns, they're parts 1 and 2 of one large story concluding the current conflict
that in mind, I really like the 2-3 campaign, though the first game obviously has the most complete story on its own
that said, I'm very irritated with this shift of emphasis to multiplayer, by all means have multiplayer, have the best multiplayer you can make-up to the point where your singleplayer team is underresourced, that's when you've gone too far with it
I think Reach will get the best of both, though, given that it's the last halo game they're making and they've talked in vidocs about how they want it to be the best one and how they want to go out with a bang
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We do not experience fear, but we understand how it affects you-Legion