Al principio de los tiempos de la humanidad en el universo del Avatar al recibir el poder de los cuatro elementos (tierra, fuego, agua, viento) fué destinado a ser el salvador de la humanidad, pero de lo que no sabían era que había sido destinado a salvar multiversos.

Gon couldn't handle the pressure of seeing Kite's body so he runs away. Killua followed him, so as Knuckles and Shoot. He hides in a cave where a mystical accident happens and the four hunters are teleported to a new world full of people who call themselves Benders. While there they will help the young Avatar Aang find his destiny as Avatar while also find a way back home.

At the end of the final battle with Killua and Illumi, Illumi throws his little brother into a dark abyss almost killing Killua. With no way out a mysterious force transports him to the avatar world. By making a wish to be free of the grasp of his family, going on a journey again after Gon parted ways, meeting new people, and becoming stronger. Kill ends up with the avatar group.