Buildings are the main system to unlock towers and upgrades for use during the tower defense gameplay. Most buildings are purchased with City Cash, take a certain amount of real-world time to build, and reward experience once construction is complete. They can have conditions such as requiring a certain City Level or only being buildable on certain kinds of terrain. They are divided into multiple categories:
DecorationsBloons Monkey City (multiplatform) are similar to Premium Buildings, but allow for more customization and come in different types. Some are purchased with City Cash, others are only obtainable through events or in-app purchases.
City Level is the main leveling system in the game. Increasing it provides additional starting cash and lives, as well as extra City Cash and Bloonstones per level. Leveling up is required for unlocking new towers and upgrades, as well as building additional MvM BuildingsBloons Monkey City (Flash), Monkey Buildings, and Resource Buildings. Capturing tiles as well as constructing buildings and researching upgrades earns experience which is required to level up.
The tower defense gameplay is based heavily on Bloons TD 5, sharing most of the same towers, upgrades, Activated Abilities, Bloons, and game mechanics, with some balance changes to towers. Unlike in BTD5, rounds are randomly generated based on the difficulty.
Monkey Knowledge is a system that unlocks permanent enhancements for towers and general gameplay. Monkey Knowledge is progressed by opening Monkey Knowledge Packs that contain XP for random Monkey Knowledge categories. Knowledge Packs can also contain other rewards such as City Cash, Bloonstones, and more Knowledge Packs.