.
Hardest part is the first phase when they stick.
Magic attacks can still penetrate his shield, but the damage will be lowered.
This is an area-of-effect shockwave attack, and it's also the beginning of a four-hit combo, meaning it's deadly if you get caught out by this first strike.
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In phase 2, dodge through his flying charge attack to as to not get hit and beware of his tail swipe, which has a high chance to be triggered when he is attacked from behind.