If you go to Magicka's official web site, you'll see that it's listed as an "action-adventure." I don't know if this is clueless marketing, or if it's intentionally misleading to try and sucker in a few extra sales, but Magicka isn't in any way, shape or form an adventure. The closest thing it has to a puzzle is when you have to freeze some water so you can cross it. Because you play a wizard in the game, you might wonder if perhaps Magicka is really an action RPG in disguise, but no, it's not that, either. With no quests or character building or much in the way of equipment, Magicka is pretty squarely an action game -- and, as far as I can tell, one aimed at masochists. I gave the game a try, but it sapped my enthusiasm quickly, and about halfway through the campaign I decided it wasn't worth the aggravation. So feel free to take this review with a grain of salt. I didn't finish the game, and I'm probably not a part of the game's target demographic anyway.
Magicka takes place in the mystical land of Midgard (a location I haven't seen since my days of playing MUDs). You play a wizard from the Order of Magick, and when bad things start happening in the land, you're sent to investigate. After defeating a collection of goblins, orcs, and trolls -- with, of course, some associated bosses -- you discover that an ancient evil wizard named Grimnir has broken out of his chains at World's End, and that it's up to you to stop him before he can take over the world.
The best part of Magicka is the magic system, which involves the use of ten basic elements: arcane, cold, earth, fire, ice, life, lightning, shield, steam, and water. These elements can be combined and cast in a variety of ways to give you an impressive array of available spells. For example, fire is by default a "spray" element, and if you combine it a "projectile" element like earth, or a "stream" element like arcane, then you can greatly increase its range, as well as add in extra damage types. You can also cast spells in a direction, or on the ground for an area effect, or on yourself, or on your weapon. During the course of the game's campaign, you'll find several books that will show you special magick spells (including haste, nullify, and conflagration), but I'm guessing for some people half the fun in the game will be in experimenting with the elements to see what's possible and how damage can be maximized.
Where Magicka starts to have some trouble is how you actually control the magic system. Eight of the elements are mapped to the QWERASDF keys, and you cast spells by pressing some combination of those keys, plus perhaps one of the three mouse buttons, plus perhaps the shift key or the space bar. As an example, for the conflagration spell, you have to type FQFFQFFQ and then target the spell and press the space bar. Special magick spells (like conflagration) are cast with the space bar, other offensive spells are cast with the right mouse button (pressing shift first if you want the area attack version), and spells you cast on yourself use the middle mouse button. You can also interact with objects using the left mouse button (pressing shift first if you want to attack), and you can block by pressing the control key. The versatility of this system is great, but it just has a whole lot of keys and mouse buttons to keep track of and use, and there aren't any friendly hotkeys available for casting spells, and so unless you're nimble on the keyboard (and don't mind typing something like FQFFQFFQ over and over again), the system gets a little tiresome.
Magicka also has an issue with its campaign, which isn't exactly forgiving. The campaign is made up of 13 levels, each of which takes about an hour to complete. A few times during each level you trigger a checkpoint, and then if you die (or rather when you repeatedly die), you go back to your most recent checkpoint. I don't really like checkpoints in any game, but in Magicka there aren't nearly enough of them, and so you have to repeat battles all the time, which isn't fun. Worse, when you exit the game you can only re-start the campaign at the beginning of a level, and so Magicka isn't a good game if you only have an hour here or there to play. If you can't complete a level in one session (which isn't unlikely given some of the difficult battle sequences) then you'll just have to start over the next time you play, which, again, isn't fun.
Perhaps Magicka's saving grace -- well, other than its price, which is only $10 -- is that you can play it cooperatively with up to four people. All the spell damage you do can hit everybody, including your allies and yourself, and so if you get four people spamming spells, then the game might get a little bit crazy, but in a good way. However, after grimacing my way through as much of the game as I played, I had zero desire to test this out, and so I'll leave it open to speculation.
Overall, I was not a fan of Magicka, even at its modest price. The game looks and sounds good enough, and it even has some funny scenes (including a vampire who keeps insisting he's not a vampire, and lots of fake-ish Swedish dialogue), but the actual gameplay was just too punishing for me. My fingers aren't nimble enough to spam things like FQFFQFFQ and FDFQDF over and over again, and the lesser (and shorter) spells I tried eventually limited how far I could go. Somehow Magicka won a Game of the Year award in Sweden in 2008, so at least some people out there like it, but not me. I got Magicka'd out in a hurry.