Curse of the battalion

The forgotten medieval sewers are guarded by a battalion of rats that have been cursed for as long as their sharp little minds can remember. Over time their ranks grow in the relative peacefulness of their moist tunnels. Yet every time the hairy battalion leaves its guard down after years of prosperity catastrophy comes. Inevitably a devastating wave of rainwater and human waste storms through the old tunnels. Merciless is the wave and it washes away the weak… Leaving behind only the bravest to face the next inevitable cataclysm. Some legends, among the depth dwellers, prophesize the birth of the one. The one that will, for the first time swim against the current and rise to the source. Up upon the bright sun-burnt lands where there is nothing above. He will reach the origin of disaster and in mighty glory destroy it ending once and for all the malediction of the battalion.