I'm planning a game to make. Want details? Hmm, maybe later.
Really do need details about the game itself if you want feedback on it.
With regard the writing only one thing stands out as jarring to me.
They end our lives, I'll end theirs. How dare they end the life of my son. The human race is dying, and so, I must end Monsterra. I must destroy each and every single one of them. Including the Seven Mythical Monsterra. Goodness knows how I am going to do it without capturing them for my own. So, I will capture them, and finally, kill them. I could sap their powers, that's it! I will build a machine that can sap the powers out of all seven Mythical Monsterra, and use it for my own! I can create a world of my own, make it happen the way I want it, I can be the god of all!
Specifically the motive translation from that of survival/revenge to that of I can be god and do things my way. Don't get me wrong, motives can and do change just not necessarily in a context such as this (an exception to this being if said character is a little off his/her rocker).
Looking forward to more