The Prototype Absolute Defence: Blade of Reflections is a magic spell that protected the coffin of Clavis Alucard.
The spell itself is activated when an intruder comes too close to an object which has the enchantment. When activated, Blade of Reflections will produce a copy of the intruder for them to battle against; in usual circumstances, this would end in a stalemate, forcing the intruder to retreat. Yuuki Terumi battled against a copy of himself created by this spell and won, taking the Hihiirokane that lay within the coffin.