Summons Master - Confrontation Of Kiri And Kumo - S1.E18

Shiroi Kumo's elder brother Akai Kiri (Madoushi) is reserected by Oscha. The main party lands in the clouds only to be attacked/paralyzed by Madoushi. Kumo appears and we learn Kiri was killed protecting his homeworld from Chaos and he wants to challenge his little brother for the title of the strongest between them. Kumo reluctantly battles his brother, smashing Kiri's sword (thanks to Kaze's help), which contains his very soul. Kiri then tells his brother to finish what he started then he disapears. Kaze and the others are set free and Kumo and Kaze are about to battle when Pist decides it would destroy the ocean puzzle and he transfers the main party and the comodeen to a new area, leaving Kumo standing looking out on the remains of his homeworld