On Ludus, ancient terror beasts and humans somehow coexist in perfect harmony. Yet once every few hundred years or so, a predictably unpredictable astrological phenomenon occurs wherein some angry people from the sky arrive from their dimension, "Terra". Whenever they arrive, a fleet of floating islands are brought along and make up the battlefields where the humans and the beasts battle for the amusement of the angry Skygods.
Welcome to Monstro. A fully deterministic logic game which plays like a tactical RPG but without RP, character growth or randomness. Fight the opposing army on the battlefield, which just so happens to be made up of conveniently perfect squares. Survive the onslaught and strike back to be the last one standing. Or, occasionally, do something else the evil Skygods want to be done for their own amusement.
It is like chess but the units have statistics and your opponent is noticeably dumber than the average grandmaster.