I never had an Xbox, so really only grew up playing Halo Reach (I think) co-op when I’d go to a friend’s house. But I recently played through most of the halo games with a friend and I have to say, I agree. I can’t remember any particular moments or scenarios, no part of the story that stands out in my mind, etc. It was perfectly fun to run through most of them (though we did get tired of it, which is why I said “most of the games”), and I can certainly see why for when they came out, they received the attention they did.