I have some sort of bias towards this fight. Gameplay-wise, it's nothing special, but it looks awesome taking an airborne giant down with a sword penetrating the sky. It's also neat that you can give those Storm Beasts a taste of their own medicine.
I lost storm ruler - was overburdened when trying to grab it, and it dissapeared next time i entered boss arena (PS3 game). I had to kill storm beasts with soul arrow (10lvl magic), and then killed Storm King with compound long bow +5 and heavy arrow. It took less then 20 arrows to kill boss.