At Heaven's Arena, Hisoka challenges Chrollo, who has become a Floor Master to a duel. Chrollo decides to have a fight to the death, to which Hisoka consents. The battle begins with Chrollo using Black Voice, which he apparently stole from Shalnark, to manipulate the referee. Hisoka realizes that Chrollo was using the time he spent fleeing from him to steal more abilities. Chrollo has the referee attempt to restrain Hisoka so he can hit him with a needle. Hisoka deflects, but Chrollo uses the opportunity to launch a series of stomps. Hisoka figures out that the purpose of controlling the referee is to tire Hisoka out and strike while he's weak. Hisoka attempts to slash the referee, but instead, the referee detonates.
Chrollo reveals his ability: Sun and Moon, which allow him to imprint seals with either plus or minus on a target, and when the opposite seals meet, an explosion takes place. Chrollo also demonstrates his other ability: Double Face, which allows him to use a bookmark to keep the page of the ability that he's using. With this, he no longer has to hold the book open to use that ability, though he can use two abilities by having the book open to another page. However, there are limitations to this. Chrollo says that he will start with Sun and Moon, and introduce three more abilities, a record for the most abilities required to kill someone.
The Sun and Moon: A sun with a plus on his left hand, and a moon with a minus on the right hand. By touching the intended target, he can mark them with a different symbol depending on which hand he used. When the two marks touch each other, they trigger an explosion.