"In a distant future, the greed of Humans brought themselves to their ruin by destroying their own land and nature, while critters with intelligence established their own civilization. Different from human race, the critters were pure and peace loving creatures, and spent a millennium in peace. Meanwhile demons were struggling to find evil minds which they have used as source of their power, once that was full all around when the earth was full of human. To bring back a world full with hatred and anger, they brought the wicked Humans back as undead creatures to invade Critterland. Knowing nothing but peace, Critters had not prepared any defenses and were mercilessly killed. The world became full with demons and the fate of the nation seemed grim. At the very moment everyone was about to g