Magicka is fun! The most powerful beam spell is QFQFASS. If you need a strong beam faster than it takes to combine the elements to get that, the Mighty ASS Beam is another good one to use.
Note - learn how to imbue your weapon with spells, and imbue it with Mine spells. When you cast them, you sling them out in a straight line like that.
Shield -> Arcane -> Water -> Fire -> Water -> Fire -> Lightning is a very damaging set of mines, and if you can make big-health enemies walk across each one, it does loads. You'll also be wailing on them while they're marching across it, too, so even *more* damage!
Consider using an Ice Beam on targets that get hit by your Steam Lightning Mines - you'll freeze them in place so you can deal with them later.
Multiplay is going to be required once you hit about Chapter 11, because there's just no way to kill the Yeti's and Trolls you'll be fighting by yourself when they start coming two at a time.