King Cold, Transfer of Power

[Critical] [Permanent] For every 2 green Extras in your Battle Area and/or Drop, reduce the energy cost of this card in your hand by 1. [Activate:Main] [Once per turn] Choose 1 green [Field] Extra with an energy cost of 2 or less in your Battle Area and place it in its owner's Drop : Choose up to 1 of your opponent's Battle Cards and KO it, then add up to 1 green [Field] Extra with an energy cost of 2 or less from your Drop to your Z-Energy.