Incognito Bloon

The Incognito Bloon comes when there are a lot of bloons on the screen (in the hope that you are distracted). It then places itself somewhere on the path and makes itself look like a tower (which may be random, or may sometimes be whatever type of tower you have the most of). It then starts "attacking" the bloons in the way that the real tower it's disguised as would, but doesn't actually do any damage to them. As soon as all of the bloons in the round are gone, it starts attacking your towers, doing 5 damage per second. To get rid of it at that point, you must "sell" it (but you don't get any money). However, if you notice it while there are still other bloons on the screen, and upgrade it, it will become confused and will think it's actually a tower. Then it will act as though it is a real tower for the next 10 rounds (but cannot be upgraded and will not give any money if sold), at which point it will go back to normal (not doing damage to the bloons, but attacking your towers when the bloons are gone). You can trick it again by upgrading it in the round in which it turns back (and then it will act like a real tower for 10 more rounds). If you manage to get it to a Tier 4 upgrade (which would take at least 40 rounds, at one upgrade every 10 rounds), it will become so confused that it will continue to act like a real tower for the rest of the game.