Regen Farming

Regen farming is a method of gaining money, but is very risky. It is based on the regen bloons and is only available on BTD5, BTD5 Deluxe and BTD5 IOS. It is based on the fact that if a Regen Bloon gains a layer it doesn't give any money when popped but it it spawns 2 bloons they will give you money when popped. Ex: a rainbow regen bloon is popped into two zebras. After some time the zebras will become rainbows and with that they will multiply.

Method
If you use the corrosive glue the bloons will pop but a short time after that they will grow a new layer. Another method is to use Summon Whirlwind. The bloons will pop some layers and the tornado will bring them to the entrance and by the time the reach the Air Disciple the will have multiplied. This can also be done with Tempest Tornado, but it is best to only use a single master of air for this, or otherwise the bloons will either get popped right away, or likely overwhelm the player's towers. The player can also farm with arctic wind and ninja monkey with Distraction. The arctic wind will give the time for the bloons to multiply and the ninja will pop them and send them back to the Arctic Wind. It is bad to use Regen Farming with Ceramic Bloons, as the bloons will take 10 hits to be destroyed and they will immediately regain the 10 HP of a Ceramic Bloon. It is also dangerous to do it if you don't have a strong backup tower to pop them if they get to be too many. You can regen farm on rounds 31, 42, 49, 51, 56, 61, 62, 69, 72, 76, 79, and 82.

Trivia

 * It is the only way of getting a Temple of the Monkey God on the sockets of power on The Crucible (Discounting premiums).
 * It is also the only way of getting a Temple on Round 31.
 * may crash your game in Bloons Tower Defense 5 iOS, if you take too long on a Round.
 * A Monkey Ace with Ground Zero can instantly get rid of all of the bloons on screen