Thanks very much everyone for the tips. I recently discovered the primary stat saving throws on spells. I'm not into magic and was struggling with the spell casters. Their spells never seemed to work. Then I looked at the spells in the actual spell book and it shows quite clearly what stat the target uses when they roll against it. There's a little shield icon even. None of that is on the spell's tool tip (on Xbox anyway) which is why I hadn't noticed. It was like Ohhhhhhhhhhh!

And it's also important to be aware of the stat used to cast it? I should be careful of what scrolls I'm giving to Shadowheart then.