Felix is a shy little beast growing up in a world where monster wrestling is the biggest spectacle there is. Lonely, and constantly bullied by the bigger monsters his age, Felix struggles to prove themselves and find their place in the world. Their fate is changed forever when a dare lands them on the doorstep of one of the scariest monsters in the whole world-- Macabber Tails, one of the most famous monstering champions in history. Felix wants to be big and brave and strong and tough, just like Macabber, and so they decide to do whatever it takes to not be a fraidy little monster anymore. Their unlikely journey together sends them to Macabber's hometown, to the mountains of the colossal flame-wielding Kilnver--a monster able to make an army of knights out of just its own saliva--and to the lair of the dastardly Amaret, the monster that made Macabber the champion they are today. Together they face some battles for their life, but not always in ways that are physical and by the end, Felix and Macabber may learn a thing or two about being tough.