Legacy of the Resourceful Hero

A hero by the name of Cereo is summoned from a cube moments before the entirety of Sabarum is laid to waste. Using nothing but his resourcefulness, he creates incredibly powerful gear and weapons on the fly using whatever he manages to find. Whether it's grass, dirt, sand, or - anything else! He manages to construct gear superior to even that of legend. Using his unrivaled skill, he defeats onslaught after onslaught of demonic and monstrous armies, eliminates disease that plagues the world to a seemingly unstoppable degree, and takes care of any and all problems this dangerous world seems to currently face. But... as the opposing force progressively becomes more difficult to fend off, Cereo comes to find out that this gimmick of his is not all that it takes to protect Sabarum. Furthermore, he begins to question whether or not the protection of this land is what's truly important.