It might be nice to make the Iron Cage have 1 input slot, that accept Pokeball w/ mob inside.
The Cage should then render the mob, with a "random" movement to make it "move".
It could use the same scaling as Mob Spawner, but only be decorative

What do you think?

Yeah I think it is a cool idea. Working on it now.

bbf751c closes this. Should be up on curse soon.