Ryomen Sukuna no Kami

Ryomen Sukuna no Kami is an ancient demon summoned by Chigusa near the end of the field trip arc. Negi attempts to defeat it using Jovis Tempestas Fulgariens but the spell failed to even penetrate its magical barrier. It was then destroyed by Chachamaru and Evangeline using a barrier piercing shot and the ice spell Kosmike Katastrophe respectively.