Lunar Black Sky(ルナ・ブラック・スカイ; Runa burakku sukai) is Berolina Gremory's Ultimate Attack, said to be her trump card against a tough opponent. By mixing her three different heritages between Bael, Alastor and Paimon, she can create a massive sword made out of Power of Destruction, serving as both a weapon and a ranged attack. By completely harmonizing the powers within herself, Berolina can create a technique that, according to mary Beelzebub, can pretty much match and even defeat a Ultimate-class devil if struck.