MDA & 8 Kinds of Fun (Anna Chang)

Bloons Tower Defense is a tower defense game where your goal is to pop all of the balloons that move across your map before they become out of reach. 

The basic mechanics of the game include placing towers, adjusting which balloons each targets, and upgrading them with coins you earn by popping balloons. By completing games (passing a set number of levels depending on the difficulty), you earn points that contribute to your overall player level and ranking on a leaderboard. 

The mechanics create a dynamic where the player must make decisions on what towers to purchase with their limited amount of coins. They also must strategically place the towers to cover a suitable amount of the map and adjust which balloons each tower targets (the balloons that are the strongest, closest to the end, furthest from the end, or closest to the tower itself). Although Bloons Tower Defense is a single-player game, there is also the dynamic of completing different maps and leveling up to move up the leaderboard.

There are a few types of fun that result:

1. Sensation: Something I really enjoy about BTD is the sound of the balloons popping. As you progress through the levels and more balloons are sent your way, the sound gets louder and louder, which I find really engages the player.
2. Challenge: Especially when playing more difficult levels/maps, the user must figure out how to pop certain types of balloons. (For example, purple balloons in BTD 6 are immune to energy, fire, and plasma attacks, which could very well be your entire layout.) Figuring out these combinations/strategies and passing tough levels is a large part of what makes this game fun.
3. Expression: Something I love about BTD 6 are the “Hero” towers: special towers you can collect with the in-game currency. There are additional skins you can get for each Hero tower and the selection is quite large. Although the game inherently has a lot of ways for the players to express themselves (through the placement and selection of their towers), the Hero towers take it to another level.