|Manga debut||Chapter #17|
|Anime debut||Episode #20 "Black Blood's Resonance War! Small Soul's Large Struggle to Oppose Fear?"|
To initiate this attack, Crona must firstly cut himself/herself in the wrist, exposing the Black Blood. Then through a simple flick of the wrist or flinging of the arm, the pooled blood is sent flying rapidly towards the opponent, while Ragnarok exerts his control over the blood forcing it to harden so as to create a crescent shaped projectile blade. This attack can also be used in close-range as a blade that remains attached to Crona's arm, allowing for numerous subsequent attacks. However, the real advantage of this variant is in it's ability to selectively liquefy at Ragnarok's will, completely negating the enemy's defense, by liquefying at the moment of contact and being proceeded by another technique, such as Bloody Needle. The two variations of the attack can be preformed in quick succession to produce a very potent combination, as the opponent is forced to focus on evading the initial projectile, not realizing a second strike is to follow. The blood used also takes the black appearance with the purple aura, that is featured in all of Crona's attacks.