What a Ruthless Mage

There are ferocious sea monsters here that cause harm to all living beings, stretching for thousands of miles along the coast; there are dragon flame giant lizards that burn down cities; there are hidden giants that crawl in the mountains and are ready to start war at any time. Humans don't have strong bodies, but they can rely on magic to hold on to the city walls. This is a war between races, this is the world of mankind's new magical civilization!