New Champion Idea

I have an amazing champion idea. My champion will be from the void. His name will be Ditto, meaning you too, and his nickname will be The shapeshifter. His Passive will allow him to steal another champions move set except for their ultimate. His ultimate ability will allow him to shapeshift into any enemy or ally champion or minion for 1 minute and steal their entire move set for the time being. The enemy team, if chosen to be an enemy when ulting, will not be able to attack Ditto unless he attacks them, revealing himself as the enemy. If you make this a champion that would be AMAZING! I think he will be awesome, let me know what you think.