An endless maze of shafts, where the only light comes from a strange luminous moss. Often taken by wild animals as their homes, many mutants have been driven to living in them by those who see them as "different" or "dangerous". Deep inside them, mutants from all over have banded together into a rough city where the strong thrive and the week go to a quick grave. Do not expect mercy or pity from those who live here, new commers are fresh meat.