Thanks for your reply, I've had a look at the perk edit form, specifically at the "Master Destruction" perk trying to see how they have edited spell cost. I've edited the entry point as you said, but I don't fully understand what the conditions mean? In your example is the value "Magicka" the actors current max magicka or is it their current magicka? What I am trying to do is have the spell cost, and hopefully damage, scale entirely with max magicka, and seeing as you said you can't use a continuous function, I'm not sure I'd be able to do it, at least not the way I'd want to. Thanks for your help!