One of the finer games released for the Wii; it needs the Wii's controllers, versus tacking it on; but it's very hard.
You'll start jumping and remember Spyro 1 on the PSX. It's just the way Dewy moves and the feeling of jumping, using his forms and various attacks.
And then you find yourself trying to navigate a series of blocks that fall from under you, and you're a sliding droplet of water with relatively imprecise control (you are sliding where you tilt the Wiimote, not walking exactly where the analog stick says as in Spyro or Mario 64).
After the first boss you'll find yourself trying to not fall off of a narrow wooden bridge, that has curves and turns, and enemies that require you to turn into ice form (which is far more slippery) in order to beat them.
Sadly, Dewy's Adventure could have been great if the developers kept the game difficulty equivalent to the tenor of the game, which is light-hearted and fun. Instead you are met with some maddeningly difficult scenarios early on, and things get worse from there.
The saddest thing was watching my 3 daughters want to play Dewy's Adventure, and having even my 10 year-old, who crunched through 300+ missions of Final Fantasy Tactics Advance and enjoys hard games usually "because I don't like games where I just push buttons and win," give up. None of them can play it.
If you're hardcore, get it. Otherwise, beware of the above.
MULTIPLAYER:
My kids and I tried this and it was a bit of a joke. The levels are square, versus the organic, large layout of the single-player game, and it's so easy to fall off all my 10yo daughter or I had to do was let the younger ones fall repeatedly. That and my ability to get to stars first beat my 10yo girl. Using powers on each other did not work well - you could either avoid the enemy player too easily or just fall off something while trying to do so.
MUSIC:
Appropriate and, oddly, really good. Catchy up-beat tunes.
GRAPHICS:
Depth of field, the watery effects, the artistic style and presentation make this one great looking Wii game.
CONTROL:
Spot-on... if only the courses were not so maddening.
COOL FEATURES:
Take snapshots in game and mail them to your friends (who have Wii's). The usual unlockables.
That's all that's relevant.