If the person who made the greatest contribution is 3 or more Lv.s higher than the raid monster, then the item/Adena rewards will decrease. If the difference is 9 or more Lv.s, the monster will drop nothing at all.

This supernatural wind tore through ancient Hellbound, filled with evil spirits and possessing a malicious will of its own.

They are not necessarily creatures, but elemental energy beings. They basically belong to the 4 elements, which are water, fire, wind, and earth, but they also dwell in natural objects. They are known to be governed by the gods of water, fire, wind, and earth.