Sunny played hide and seek with the Snow Worm by jumping between shadows while the mountain was falling apart around them. The creature's gargantuan size made it difficult for him to destroy its body... but it also made it difficult for the creature to destroy him.
The pale, segmented coils of the Snow Worm were wrapped around the entire mountain many times over, expanding and constricting as they moved at great speed and slowly ground the mountain to dust — because of their sheer mass and number, the Cursed Beast was its own obstacle when hunting down an adversary as mobile as Sunny.