The game is a classic type of tower defense game in which the enemies follow a predetermined path on each level. All enemies in the BTD games are balloons called bloons. In the Bloons TD series, it only takes one hit to pop a bloon, but as levels progress you'll be met with bloons inside other bloons. The basic tower, called a Dart Monkey, is a monkey throwing darts at the balloons, similar to the original Bloons game series.
There are 12 types of towers and 4 single use items. All towers can be upgraded and gain additional functions. You can change the targeting mode on each individual tower to "first" or "last", which is useful for towers with piercing abilities. Placing towers can be tricky as there's no grid system, so sometimes you'll have to find just a few available pixels to place towers on in tight groups.
There are eight maps, but four of them can only be played from Ninjakiwi. Some tracks feature bloons coming in from multiple paths at once. Each map can be played on 3 difficulties, Easy, Medium and Hard. Should the player beat all waves on a map, there is a "free play" mode available after you complete the level, allowing the player to continue playing indefinitely.
- Red - First encountered bloon.
- Blue - Spawns Red
- Yellow - Spawns Green, Fast.
- Pink - Spawns Yellow, Fast.
- Black - Spawns Pink, Immune to bombs.
- White - Immune to freezing.
- Camo - Spawns 2 pinks, Need to be detected with Monkey Beacon.
- Zebra - Spawns White and Black, Immune to bomb and ice.
- Rainbow - Spawns 2 Zebras.
- Lead - Spawns 2 Blacks, Slow, but immune to anything sharp
- CB - Takes several shots to destroy, spawns 2 Rainbows. Glue doesn't slow them.
- M.O.A.B. (Massive Ornary Attack Blimp) - Even stonger than CB, looks like a blue airship. Spawns four CBs.
- Dart Monkey
- Tack Shooter
- Ice Ball
- Monkey Beacon
- Super Monkey
- Road Spikes
- Monkey Glue
- Top Secret Weapon (monkey airstrike)