If the level of the person who made the greatest contribution is higher than the level of the raid monster by 3 or more levels, then the probability of dropping an item or adena will decrease. If the level difference is nine or more levels, then, the monster will not drop any item or adena.
Raid Boss - Level
A devil and Beleth's inferior living on Devil's Isle. After Beleth disappeared from the world, this devil stopped his activities on his own and has been taking a long vacation. When the pirates occupied Devil's Isle and became noisy, he woke up and regretted that he didn't wipe out the pirates from Devil's Isle before Zaken became immortal. He is waiting for his owner, Beleth, to come back again and give him commands.