Which magic type hurts the worst? Super heated Pyroblasts? Searing holy power? Ice-laden Frostbolts?
My list (most to least painful)
Shadow/Unholy
Fire
Arcane
Frost
Nature
Holy
Shadow is probably a mental pain more than a physical, which is why I'd give it the nod over fire. Holy, likely just feels like standing near a heater. It's warm and cozy and you don't immediately realise it's killing you.