The Understreets are the collection of tunnels that lie below Heavans Peak. The Blue minnions can be found here. Enemies include a sea serpent, beetles, bomboo birds, and others. The durium smelter is also found here. Be careful with your minions here, because its an undead fiesta down there. Be advised to use red minions and a fire spell, but keep the zombies far away. Be sure to keep your minions alive, as there are very few spawining pits.