Darianius will drop Unholy Claw or Dark Claw and a Crystal Shard, there's a chances that Darianius will drop both Claw. Darianius is One of the Four boss require to kill in order to make Magic Vault become vulnerable to obtain Magic Urn. If Darianius is killed, you may now near the Tomb to obtain the Death Seeker. If Darianius is Defeated, you may now fight him in Battle Arena as "The Sacred Tomb", His items in arena is remain as same as original.