Leorio and Kurapika witness Hisoka's violence. While they initially run, returns to fight, unable to ignore the cruelty.
A group of applicants surrounds Hisoka, attempting to disqualify him because he is too dangerous. Hisoka decides to play "examiner" himself, slaughtering nearly all of them with his razor-sharp playing cards. Gon and Leorio vs. Hisoka: Hunter X Hunter 2011 Episode 5
Hisoka is impressed by Gon's potential and Leorio's courage. After knocking Leorio unconscious, he tells Gon they both "pass" his test. He carries Leorio to the next exam site himself after receiving a radio call. Leorio and Kurapika witness Hisoka's violence
Applicants are ambushed by various monsters, including Noggin Lugging Tortoises (which use strawberry-like bait) and the Frog-In-Waiting , which briefly swallows Gon and Killua before spitting them out because of the spiked juice Killua carried. After knocking Leorio unconscious, he tells Gon they
In the manga, the does not actually swallow Gon and Killua.