User blog comment:Jopjopjop/Volume 20 Spoilers/@comment-24421137-20150719030548/@comment-24502975-20150719054409

Nope, it was Fafnir. He broke both Rizevim's legs and then broke his neck/decapitated him. This was after Ise hit him with Infinity Blaster and EJOD Vali cut off his left arm.