Before entering the Greed Island game and beginning their Isekai arc, Gon and Killua must learn how to specialize their nen with Hatsu. Even while Killua seems to grasp what Hatsu is and how to get it, he refuses to offer his companion any suggestions. Perhaps Killua thought his silence would drive Gon, but when the enhancer was forced to seek guidance from Wing, it became evident that Killua was actually hurting his buddy. Gon may not have been able to join the Greed Island game if he hadn't sought out to his old instructor for help. Killua's stinginess with his information was a little impolite given that the main goal of playing the game was to identify Gon's father.
