An ursikka can enter a prolonged state of hibernation by surrounding itself with its spittle, which hardens into a cocoon. While hibernating, an ursikka doesn't need to drink or eat. The cocoon has hardness 10 and 60 hit points, and is immune to fire damage. As long as the cocoon remains intact, the ursikka remains unharmed in its hibernation. An ursikka must use its attacks to break free from its cocoon.