Sorry for the non-discript name but here is the plugin idea: Whenever you kill a mob (hostile or not) you gain access to that mob. If you do /disguise it would open up a large chest full of spawn eggs and stuff like wither heads and enderdragon eggs. It would have one thing to describe each mob. The name of the egg would be the mobs name and red if you don't have it and green if you have it. You can unlock a mob by killing that mob. When you kill a mob for the first time it would say in the chat in green magic for like 10 characters at the top and in the second line it would say in blue You have unlocked the (mob name)! You can not unlock players. Sheep only come in one color, white. There would be a permission: mde.hidename and if a player has this while disguised there name would be hidden so they could sneak around. I would like to talk to whoever would like to code this about special abilities you could do while as each mob.