New Super Mario Bros. Wii makes the arbitrary distinction of offering a "cooperative" Story mode, and a competitive multiplayer mode, but after a level or two, it's clear that there really is no such thing as cooperation in the Mushroom Kingdom. There's no real reason to switch between either mode, as both feature the same levels and a finite number of lives for the players. The only real addition to the competitive mode is the scoreboard at the end of a level, which ranks players based on their score, coins collected and the number of enemies defeated.
Why do we say there's no real cooperation in the Mushroom Kingdom? Simple: there are so many ways of being murdered in NSMBW. You can grab a fellow player and throw him down a cliff, into an enemy or into some molten lava. Grab a Yoshi and eat your friend ... and then spit him into a Piranha Plant. They won't be your friend anymore! You can even kill someone before they get to live a full life, by finding their spawn bubble and destroying it in an -- ahem -- inconvenient place (over a pit, perhaps?).
Even if you try and play like friendly, civilized folk, you'll find it difficult to not inadvertently murder your friends. Each of the four playable characters (Mario, Luigi, and both a blue and yellow colored Toad) can bump into each other. You might accidentally jump on a friend mid-jump and have him plummet to his doom. A small moving platform may only have enough room for one or two players, let alone four. The game encourages conflict, both intentional and accidental, and that's what makes it such a joy to play.
There is some cooperation necessary, because if all four players expire before a new player can respawn, it's Game Over for everybody. We saw this dreaded screen three times during our private preview session. (It was all Dan's fault!) There's no real penalty for dying, though. Yes, the game does keep track of the number of lives you have, but a Game Over doesn't make you lose any progress. You'll know how many Game Overs you've earned over the course of the game, but without any achievements or leaderboards, you can keep this information all to yourself.
New Super Mario Bros. Wii is not a graphical tour de force, nor does it need to be. While some will complain that it looks nearly identical to the DS game, we have to commend Nintendo on creating a dynamic camera that zooms in and out, depending on how far apart the players are. Even with all the chaos on screen, it's easy to keep track of your character. Should you lag behind so much that the camera no longer shows you on screen, your character will be KO'd -- so make sure you don't take too leisurely of a pace.
Even without multiplayer, NSMBW looks to have all the trimmings that a hardcore Mario fan needs from a game. Each level is filled with secrets, and players are encouraged to search every pipe and block to find alternate routes. Like in the DS predecessor, there are three special gold coins in each level that players can seek out. The SMB3-inspired world map is bound to hide a few secrets (and levels) as well.
No Mario game is complete without zany power-ups, and NSMBW brings a few new ones to the table: in addition to the requisite mushroom, fire flower and star, there's a new ice flower that allows Mario (and his cohorts) to freeze enemies. This is helpful in underwater levels, as frozen enemies will float to the surface, creating new platforms for Mario to jump on. Then there's the propeller suit, which thrusts Mario to the sky by shaking the Wii Remote. There's also the penguin suit, which allows Mario to navigate through the icy worlds a bit better and gives him a devastating slide attack (initiated with the down button).
The Mario franchise is so reliably excellent, that it's unsurprising how polished -- and more importantly, how fun -- the latest iteration of the game is. While we're thoroughly excited for NSMBW, the game does highlight how flawed Nintendo's online connectivity has been this generation. No, we're not complaining about the lack of online multiplayer (a valid complaint, by the way). It just pains us to think we'll have to wait years for another proper sequel, when we know we'll be begging for DLC immediately after the game releases.