Ice mass Blizzeta in the Snowpeak ruins is tough but easy if you know how. When it starts get out the Ball and Chain and swing it at her. Ice will break off. When it looks like a spinning top, she will through ice at you. Just keep hitting her. When it breaks there'll be a short scene and she will fly in the air. Shards of ice will fall at you. keep running and when they end use the ball and chain to break one. You WILL need to or when they form a circle and theres no gaps Blizzeta will smash into you. When the circle dose form, and go into the ground, go out the gap fast then turn and smash blizzeta with the chain. Do this a couple of times and eventually Yeta will transform back.

hope this helps