The Rainbow Bloon is a bloon that originally appeared in Bloons Tower Defense 2 and has appeared in every other BTD game since. It is the parent of two Black and White Bloons in BTD2 and BTD3 and the parent of two Zebra Bloons in BTD4 and BTD5. Rainbow Bloons are quite fast, having a relative speed of 2.2 compared to a Red Bloon. They are faster than White Bloons but still slower than Ceramic Bloons. In the original Bloons, there is a Helium Bloon, which is also rainbow and is often confused with this.