Dual Casting; Worth it? - The Elder Scrolls V: Skyrim - GameFAQs Dual casting takes a tremendous amount of mana ( more than double) but you still only get the single shot of whatever spell you're casting IE: Dual casting Flames, does it really do more than the normal 8+8+extra of dual casting without the perk Moreover, what the heck is the point of dual-casting alteration spells