Mouldcake is the local delicacy of Underzone and, as the name suggests, is a cake made with mould. Tails was offered some mouldcake when he accidentally followed Underzone inhabitant Zeg back to his home, but the fox refused. His reward for saving the entire Zone from a gas leak was a lifetime's supply of mouldcake, but Tails turned this down in exchange for being able to return home.