One game that I love is Bloons Tower Defense 5. Some of the mechanics within the game are its tiered upgrade system and round-to-round economy, which each create a high level of gameplay diversity even if the loop is largely the same. As a tower defense game, Bloons leans heavily on its individual units to keep the player engaged. Even a unit as simple as the dart monkey has a range of interesting upgrades that provide replayability as players try to optimize their unit and upgrade choices. Another mechanic that contributes to the game’s dynamics is the in-game economy. Each round, the player earns a certain amount of money that they can use to buy or upgrade their units. Through the use of certain units or real-life money, it is also possible to increase one’s in-game money. This tension between the costs of units and available funds also encourages the player to think carefully about each action, lending a strategy aspect to the gameplay loop.
