Not a Hero 2.0

In desperate need of someone to defeat the demon king, you and your friends summon what was supposed to be a hero to save your world, sadly, what showed up was violent, unhinged, vicious, and terrifying. He looks mostly human, but has large horns, black eyes, massive muscles, and an unkind smile. The odd thing though, is that your blood was used in the ritual, and the beast seems to be unable to harm you, he even listens to you on occasion. You now need to decide what to do with the demon, how to try and defeat the demon king ruling your dimension, and how to convince your friends that your plans are the right ones and not based off of the bond your blood seems to have created with the beast now following you. [Be sure to check the story cards when you start and edit as you see fit. There are a number of monsters made for this world included, but it may be too much for smaller engines]