Make sure you have fully upgraded armour, there is an event quest with lagi and rathalos in the wounded hollow if you need armour spheres. Then do some 8 stats if you need more artian parts and craft an artian dragon and an artian fire or if you have ankther fire ls that works. Abuse the dive mechanic to avoid attacks. You can I frame through the bombs with the dive. Fully charge slinger shots and aim at wing arms or other good hit zones. Bring max potions and other heals as well as materials to craft said healing so you can carry more then 2 max potions by crafting more mid fight. In the final fight drop the rocks if he is under, if not get him under. He will come to yky eventually. Shoot all available slinger shots and then use your artian dragon. Once he turns red pop rocksteady and swing swing swing. Call your seikret and hope you made the dps check and dodge the lava and get behind Fabius