I been looking at that stat and I have no clue what it does. It doesn't make me take any less damage from spell, so what does it even do? Does it "block" magic or something? Edit: Lol nm it seems like that's exactly what it does.
Magic resistance is basically like 'block' for magic. In terms of actual 'magical damage reduction', where actual damage is reduced, you have to rely on on how the actual spell works, and have resistances specific to that type of damage (conflagration, hyperborean, poison, etc).
When you resist a spell, a little pop up appears above your head and says "RESISTED" and take only partial damage. How much is unknown, but it is probably the same as the block formula.
Resisting magic still makes that annoying TINK sound that's shared with shield blocking, doesn't it? Is there another sound planned for that or are we stuck with that?
