The Wizard's Cave is a certain structure which spawn near swamps in the Semosphere, but NEVER near a Witches' Hut, prpbably because of the rivalry they have. They are a home to atleast 100 Wizards, and can spawn even more. There are chests hidden in these caves, which include any of these items:
Villager Spawn Egg
Bow and Arrow
Diamonds, Emeralds, Gold, Enchnatment Table, Iron, Coal (extremely rare)
Usually, there are alot of Radioactive Mix inside these dangerous looking caves. Ores can be sometimes found here, but only Iron, Coal, and Color Ore.