Monkey Glue is a roadblock that debuted in Bloons Tower Defense 2. Each Monkey Glue is enough to slow down 20 Bloons before wearing out. Monkey Glue only lasts until the end of each round. In Bloons Tower Defense 2 & 3, Monkey Glue costs 40 coins. In BTD app (For iPhone/iPad), Monkey Glue costs 35 coins. In Bloons Tower Defense 4, Monkey Glue is reduced to 10 coins. In Apopalypse Mode, Monkey Glue, as well as Road Spikes, lasts for an indefinite amount of time since there are no round endings. Ceramic Bloons and MOAB-Class Bloons are immune to Monkey Glue, as well as the Glue Gunner tower (which probably shoots Monkey Glue) without the Corrosive Glue upgrade. Monkey Glue is best used for the early rounds.