BASTARD!!: Ankoku no Hakaishin (ONA)

In a post-apocalyptic heavy metal fantasy world, humanity faces threats from orcs, lizard men, and other creatures. The only hope against these dangers is a force even more sinister. A 14-year-old boy contains the chaotic wizard Dark Schneider, who is released to confront four powerful generals attempting to bring back the malevolent god Anslasax.