Challenge Monkey

"Prepare for Challenge Monkey! An all new, limited time event that dares you to complete maps using ONLY a hand picked team of monkeys. There are amazing rewards available, if you're up to the challenge!"

- Version 3.15 description

Challenge Monkey is a new event introduced since Version 3.15. It involves using only the selected towers to gain quadruple rewards. Unlike Preferred Monkey, which involves at least using a quantity of the selected towers, Challenge Monkey shares more similarities to the Monkey Teams event in Bloons Monkey City, except Challenge Monkey doesn't necessarily allow Banana Farms or Monkey Villages.