Nintendo provided a first look at a new feature in Super Mario Odyssey during its Treehouse Live stream at E3 today. When the game ships in late October, two-player co-op will be included. One player will control Mario while the other controls Cappy. Super Mario Odyssey

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Simple but effective. I approve.

That sounds awesome, does a lot more to co-op than the Galaxy games, but it's ultimately still a 1-player adventure.

I like it.
It remains a single player game at its core, but someone can jump in and join for fun.
Works for me.

In their defense, games like these reeeally aren't meant for multiplayer... you only have to watch some of the playthroughs of the multiplayer hack for Mario 64 to see why, as in a 3d platformer camera control is absolutely mandatory; it's why they took the approach they did with Super Mario World 3D, as it had fixed cameras depending on where you were, but even then it sometimes became difficult.

Could be solved by a splitscreen, but I imagine that would tax the hardware a tad as they tend to push said hardware to the limit with their Mario releases.

I'm fine with it since its inclusion doesn't seem like it forced any compromises to the core single player experience like it typically tends to do in other situations for historically single player games (RE5 and Dead Space 3 for example).

Not the multiplayer that I was looking for but still neat to have.

That's ok, this Mario doesn't really need multiplayer.

It wasn't the type of game that would work with the type of multiplayer of lets say 3D World, but it's nice they have something co-op related.

There will be other Mario games to come that will heavily focus on the kind of multiplayer we've seen in past games like 3D World and New Super Mario Bros.

Well that's nice. Now we can fight over who gets to do what and who has to sit out. #4 the family