It turns out that Nintendo's forthcoming sandbox-style Mario title for the Switch won't just offer a single-player experience, but a co-op mode as well, akin to the co-op modes of Super Mario Galaxy and Super Mario Galaxy 2 on the Wii.

Super Mario Odyssey Will Feature Co-op Mode

We're of course referring to Super Mario Odyssey, which received the full E3 treatment at Nintendo E3 Spotlight presentation, the Nintendo Treehouse Live events, and on the E3 show floor itself — meaning everyone got a new trailer, tons of gameplay footage, and E3 attendees got to try it out firsthand.

But Nintendo had at least one more surprise: Super Mario Odyssey, as it has now been confirmed, will feature a co-op mode, with player two assuming the role of Cappy, Mario's sentient hat. Polygon first spotted the said mode during Nintendo's Treehouse Live presentation, at around the 4:27 mark.

The Other Player Controls Cappy

Showing a demo of the mode during the stream, game director Kenta Motokura said that the Switch's two detachable controllers inspired him to add co-op controls. Needless to say, the two players will use one Joy-Con each. In co-op mode, Cappy hovers at a slight distance above Mario's head, and an onscreen prompt also appears to explain the basic controls.

What Can Cappy Do In Co-op Mode?

Mario can still perform his usual moves, in addition to controlling the camera, but he will no longer be able to fling his hat toward enemies — although they did tease that Mario will still be able to control Cappy to some extent, but didn't elaborate how during the presentation. Anyhow, player two will be able to fly Cappy around and launch attacks, in addition to controlling the camera.

Having a second player to control Cappy gives some advantages, such as being able to collect quickly disappearing elements much faster, such as scattered musical notes, for example. More importantly, Cappy boasts invincibility, so playing him would be perfect for players who can't stomach dying all the time. What's more, to hone the importance of co-op mode further, Nintendo also added specific puzzles that are easier to solve with two people playing.

Super Mario Odyssey

Super Mario Odyssey, arguably the biggest Switch game to come this holiday, features a sandbox playstyle, highly similar to past Mario entries such as Super Mario 64 and Super Mario Sunshine. Game director Yoshiaki Koizumi said that was the biggest challenge they faced when developing the game — as Nintendo hasn't toyed with a sandbox-style Mario in 15 years.

"[I]t felt completely different and new to come up with ideas that would work [in Super Mario Odyssey]. We had a lot of debate to decide if people would accept [the sandbox] kind of playstyle again. That was probably the biggest challenge for us," he said during an Ask Me Anything session over the Nintendo Switch subreddit.

Super Mario Odyssey launches Oct. 27 for the Nintendo Switch.

Thoughts about co-op mode in Super Mario Odyssey? Feel free to sound off in the comments section below!