It’s a lot simpler than in the past
Just like Super Smash Bros. 3DS, the unlock conditions are fairly relaxed in the Wii U version. Of course there is at least one stage that’s hidden behind a specific unlock condition, and most of the stage unlocks aren’t apparent at first.
Although this doesn’t spoil any stage specifically, I’d refrain from reading the comments if you want to be surprised.
As far as characters go, the same principle goes as the 3DS version — they’re unlocked by completing matches. All you have to do is go in, set a match to one stock, put in a CPU, and fall off the cliff over and over until a contender arrives (which is roughly every 10 matches). Choose your best fighter as you’ll have to beat the CPU to unlock it. This should only take you a little under an hour.
The level unlocks are less straightforward. One stage is granted by playing all three boards in Smash Tour, the new Wii U specific mode. Just set the rounds to the minimum amount and play with three CPUs on each board. Simple.
The rest are unlocked entirely through event mode. As you start completing levels you’ll find new arenas. Just complete them (and the unlock condition, such as a difficulty level) and you’re good to go. So yea, it’s not as obscure as “use Kirby or Pac-Man’s Final Smash” like on the 3DS.
Trophies, music tracks, Mii outfits, and moves are unlocked the same way — just play random modes and earn coins, then buy them in the store or use the Trophy Rush mode for Trophies, and Smash Tour will grant you tons of outfits, tracks and moves.
