There are several ways to make upside down mobs. 1. Take a spawn egg of any kind place it in a anvil. Name it "Dinnerbone" or "Grumm" then place egg for a upside down mob. 2. Take a name tag place in a anvil name it "Dinnerbone" or "Grumm" then tap a mob to name it (DISCLAIMER) I don't know if the Grumm one is correct
