Green Paint is a tool that can be used to change a Red Ring, original or painted, into a green Red Ring*. To apply the paint, equip a Red Ring or Red Ring*, and use the paint in the inventory. Any painted ring will have its name appended with an asterisk (*), and also have "Skin: Green Ring" in the item description. Painted rings function identically to a normal Red Ring.
Green Paint is one of the items that can be infrequently obtained from opening a Present during the Christmas Event.
Green Paint can be obtained for 1 Season Point in the quest Seasons Shop by talking to the Guards Shop NPC.