Part of the initial appeal of a new Mario game is pressing buttons and watching what happens. In Super Mario 3D Land , the most magical button is the 3-D slider.

The Nintendo 3DS lets you adjust the “volume” of the system’s glasses-free 3-D visual effects by using a sliding control that sits to the right of the screen. If you’ve played other 3DS games at length, you’re probably used to just setting the 3-D slider somewhere comfortable, then forgetting about it. But Super Mario 3D Land , designed from the bottom up for this new display, seems to want you to constantly play with the 3-D slider to see what happens when you go back and forth between two and three dimensions.

For example: Everybody loves 1up mushrooms, those green fungal givers of extra life. When you see one sitting tantalizingly across the room, you make a beeline for it. But earlier this week when I took 3D Land (to be released Nov. 13) for a test drive, I encountered lots of fake 1ups painted on wooden boards, like theatrical backdrops. If the system was set to 2-D display, you couldn’t tell. In 3-D, you can better see the depth, or lack thereof, of the ersatz toadstools.

During my first demo at E3, I saw a similarly fake Goomba enemy and tried to jump on it, but of course ended up leaping over it. In this new demo, there was a 1up mushroom sitting high up on a pyramid, and I had to shoot myself out of a cannon to reach it. Only mid-flight, when it was too late, did I find that it was a fake.

If Nintendo intended players to just choose their level of 3-D display and leave it there (or simply turn it off and play in 2-D), these mushrooms would just be a dirty trick with varying levels of effectiveness. But I think Nintendo put them there because it wants players to have a reason to reach up and touch the slider: “Is that mushroom in the distance worth going after, or is it a fake? Hmm, maybe I’ll bump up the 3-D and see if I can tell.”

Nintendo has sold almost 27 million copies of New Super Mario Bros. on Nintendo DS. So it’s reasonable to assume that quite a few 3DS owners will buy 3D Land . Getting as many of those people as possible to want to reach over and mess around with the 3-D slider is an important goal for Nintendo, because the company is currently struggling to make the case for why 3-D in games is more than just a visual gimmick. It needs to illustrate that the screen is a game-changer.

Another example: In a later level, I went down one of the series’ trademark green warp pipes to find myself in what looked to be a simple, small bonus room: A pyramid of blocks with a bonus Star Coin on top of it. But I kept walking through the block I had to stand on. Stepping on a small panel that rotated the game’s camera around, the answer was clear: The block appeared to be stacked with the rest, but was actually floating in front of them.

A simple puzzle. But I don’t think that was the point of the room. Even after getting the coin, I sat there in the room for a while, flipping the 3-D slider on and off. Off, I couldn’t see where the block really was. On, I could just sort of see that it wasn’t really in the same space as everything else, that it was floating a little closer to me. Again, I kept playing with the slider to see what happened.

A Tale of Tails

Even besides the experimental use of 3-D elements, Super Mario 3D Land is quite a different experience from its predecessors. It might best be described as a hybrid of New Super Mario Bros. and Super Mario Galaxy . While you have freedom to move around in 3-D space, the levels are laid out in a linear fashion and you often view the action from the side. While some levels take a more non-linear approach and play with the camera angles, this happens gradually as you play through the game; clearly, Nintendo is trying to ease the casual players into the more complicated gameplay styles.

Nintendo’s always been accused of playing the nostalgia card a little too often. In announcing that Super Mario 3D Land would feature the return of the Tanooki Suit, the raccoon costume that first granted Mario the gift of flight in 1990’s Super Mario Bros. 3 , Nintendo opened itself up again to the idea that it was simply engaged in base pandering.

And perhaps it is, but there’s a solid gameplay reason for it. The Tanooki Suit, in this game, doesn’t let you actually fly. What it does is let you glide down slowly by flapping your tail. This is an attempt to solve one of the fundamental problems of 3-D jumping games: Landing in the right place. With the extra finesse of the Suit, it’s a little easier to land accurately.

That’s all well and good, you may be asking, but what if you don’t have the suit? As it turns out, you probably will: The leaf-shaped power-up items that grant you the power are scattered from hell to breakfast across 3D Land ‘s levels. And if you do take damage and lose the power, you can hold an item in reserve and access it by tapping the touch screen.

You can also shoot fireballs by collecting a Fire Flower, and if you want, you can swap back and forth between fire and flight, just as long as you don’t get hit or collect a different reserve item.

So yes, Mario will likely spend a good deal of this game in a hot, sweaty, fur suit. Just imagine how that will smell by the time World 8-4 rolls around.

3D Land is divided up into some number of Worlds, each of which contains at least four standard levels and a boss encounter. We’ve seen in screenshots that some of these levels will take place aboard an airship, although I didn’t get to play any of those. What I did get to play was a more straightforward raid on a Koopa castle, the basics of which will be familiar to anyone: Dodging fireballs, jumping lava pits and finally squaring off against the big man himself. In this level, it was as simple as dodging his fireballs, running past him and jumping on a switch to send him into the lava — a 3-D, somewhat more complex version of the level-ending fights from the first Super Mario Bros.

What took me by surprise was the first time I found a pair of sightseeing binoculars, the sort of thing you’d find on top of a tall landmark in a big city. Standing in front of them, I found myself peering out in first-person at the rest of the level that I’d have to play, getting a little preview of what was ahead. Eventually I tracked down a Toad who was hanging out by a flagpole, and when I zoomed in on him he saw me and started acting out what I was supposed to do once I got there — take a running leap off the staircase and jump for the top of the pole.

In later levels, if I spotted Toad through the binoculars he’d throw out a Star Coin, one of the collectibles that are scattered in the levels in hard-to-reach places. I’m guessing finding and using these will become more difficult but more rewarding as the game gets harder.

3-D Or Not 3-D