Sky Slime: A new flying mob that makes Minecraft farming into vanilla

This mob would be a natural way to implement item farms into the game, aswell as being many other things.

The Sky Slime is a rare white slime which has a propeller on it's head which makes him fly way above the cloud limit, where it can be found. It would be the first flying daylight mob after the phantom. It is a neutral mob, you can befriend it or attack it, which both are quite useful. 

If you decide to feed slime balls to him, it will follow you flying everywhere, except underwater. When a Sky Slime is following you, both Slimes and Magma Blocks will stop seeing you as a threat. If befriended, you can throw any type of items towards it and watch it fly away to look for that same item. He'll return with a stack or duplicate of that same item, which makes the player capable of creating a farm for any item with enough Sky Slime. Beware since the rare items will take longer for the Sky Slime to return, for example it doesn't take long to come back with a stack of Ground but it will take many days to come back for diamonds. And feeding them can grow you closer, and he may be faster to retrieve items.

If you attack it instead, he'll try to lift you and throw you from a huge distance, but defeating it grants you Slime Pearls. Which you can build White Slime Blocks with (they bounce twice as high), aswell as a propeller to go upwards or a pair of bounce boots, which make you bounce a lot on the ground non-stop.

They can also be called Sklymes if you will.