It seems like if there's one way to get people to love your downloadable game this generation, it's to make it a side scrolling puzzle platformer. Trine combines that style of gameplay with a cute if typical fantasy setting and a heavily physics-based engine to create a game that's pretty fun, although not without its frustrations.
So to start things out, the game introduces you to its three characters, which fit so well into standard fantasy niches that that's how they're named. You get a taste of the abilities of the wizard, thief, and knight before they all place their hands on the Trine at the same time, which imprisons all of their souls and fuses them into one person. At the same time, the world around them pretty much goes to hell, and they have to combine forces to find other artifacts that will allow them to remove this evil curse from the world or whatever. You can switch between the three characters at will, and you must use all of their abilities to make it through fifteen levels of platforming and combat.
There's also a co-op mode where you can share the different forms, although I was never interested enough to try it. The game works because you only need the services of one character at a time to get past an obstacle, and having to maneuver multiple people through each situations sounds like it would just slow things down. The thief is the most maneuverable, the wizard can create objects to climb over or weigh things down, and the knight is the most useful in combat. It won't be long before you're constantly switching between them based on the situation; creating counterweights or bridges with the wizard, swinging between overhanging planks with the thief, and smashing large objects out of the way with the knight.
This sort of thing is what makes the game really fun, and honestly the constant fighting drags it down quite a bit. Besides the rare larger enemy you'll see once in a while, it's pretty much all skeletons all the time, and they get boring after a while. It's not a bad idea to mix it up sometimes, but too often you'll just find yourself sitting there, waiting for the game to move on while skeletons continually spawn in front of you. And even worse than the skeletons are the occasional bats and spiders, which are designed to do nothing but irritate the heck out of you and waste your time.
The fact that the combat is mostly a drag makes any issues with the platforming stand out more, since that becomes the part of the game you rely on to provide actual fun. There really aren't many issues, although sometimes the physics seem like they're working against you rather than for you, and by the end things seem maybe a bit too difficult just for the sake it. Especially areas like the final section of the last level. They're not exactly hard, because the game is pretty forgiving, they're just irritating. In the game's favor though, it looks and sounds nice, and the story is told in a charming fairy tale style that makes the rudimentary plot more interesting. A sequel is coming, and while I'm not exactly clamoring for more after seven solid hours of adventuring, it should be fun.