The Hero Is Overpowered But Overly Cautious, Vol. 4 (light novel)

After pushing himself well past his limits, Seiya emerged victorious from his Battle with the Beast Emperor, Grandleon! But his struggles in the revamped world of Ixphoria have only just begun... Next on the chopping block is the Machine Emperor, Oxerio. The high-texh arsenal replete with tens of thousands of magical weapons threatens to plunge Seiya and Rista into the depths of despair! Fortunately, Seiya's got a secret weapon! ...Sort of.