To find out why the game crashes on YOUR computer, please find the error log and dxdiag. Either look at them yourself or attach them here so I can investigate your case. You get the dxdiag like this: run (start menu or windows button + r ) dxdiag and choose Save All Information. This will land a dxdiag.txt on your desktop that you can attach here. The error log will be in Steam\steamapps\common\magicka. Attach that as well.
If you open the error log, the most common issue will be this:
Thread: RenderThread Microsoft.Xna.Framework.NoSuitableGraphicsDeviceEx ception: Could not find a Direct3D device that supports the requested features. vid Microsoft.Xna.Framework.GraphicsDeviceManager.Find BestPlatformDevice(Boolean anySuitableDevice)
Which tells you that the graphics card is most likely below the minimum specifications.
The second most common error is this:
System.NullReferenceException: Object reference not set to an instance of an object.
Which is not as easy to interpret, but means that there is a problem with audio. See if you can make some alterations there. Use the onboard graphics instead of your graphics card. use the headphones as default device instead of the speakers, stuff like that.