FF7EC Leviathan EX2

It seems to me that Thunder God Cloud is a must have in this fight. Other than that, Leviathan will be targeting the character with the lowest HP. Therefore, you better equip this character with water resist weapons. Other important tip is to use summon and lb to interrupt Leviathan attacks while using cloud to deal as much damage as possible.
Good luck with your runs and I hope you find this video useful
Background music: FF16 Leviathan Cascade