The Bloon Combiner (Special Mission)

The Bloon Combiner is a special mission in Bloons Golden Defense. It is 30 normal rounds. However, the track has a green circle on it. Every 10 seconds, all bloons that are in there are combined into one. All of the bloons health is added, and so is their properties. When the combined bloons are popped, they release all of the children the normal bloons would have. Completing this gives you a 2/2/3 Alchemist insta-monkey.