Board Thread:Questions and Answers/@comment-54.203.204.130-20150412154027/@comment-4627764-20150413133538

They are probably talking about the Ninja Kiwi decal in Bloons TD Battles. To answer your question, decals are special decorations in Bloons TD Battles that can be bought with medallions. They do absolutely nothing and are purely decorative. You can find decals by going to Towers and Bloons and clicking the "Bloon Decals" tab.