The underdark

Author's Note: The Underdark is a vast, subterranean network of caverns, tunnels, and mushroom forests. It's a dark and dangerous place, filled with monstrous creatures and ruled by evil deities. The Underdark is a vast network of caverns and tunnels that stretches beneath entire continents. Its exact depth varies, but it can reach depths of 10 miles or more. The deepest parts are known as the Lowerdark, where strange and terrifying creatures dwell.