There are roughly four billion tower defense games for iOS at this point, and they’re all based on the same concept with a few differences here and there that set them apart from one another. I’ve tried a few, but the only one I really liked was Bloons Tower Defense. I first played it as a Flash game, which was pointless at higher levels as Flash is utter crap that hugs processing power like crazy (but you all already know that). When Bloons TD came to the iPhone a little over a year ago I was thrilled and because it’s tailored to the hardware (unlike Flash) it had no problem keeping up, which meant it was much less of a pain to play. Now they’ve released Bloons TD 4 (aka the second version of the iOS game) and it has a lot of nice upgrades, and is more fun than ever.
Unfortunately this is an iPhone game, meaning it will run on the iPad with not at the native resolution. At $2.99 I wish they’d do us the courtesy of a universal game, or at the very least an iPad version at all, but it’s not the first time great apps have gone this route.
The tower defense concept is based on defending a path from a horde of enemies who keep on coming by placing “towers”, that is, stationary “good guys” that fire various things. Field Runners seems to be the most popular one on iOS, though Plants vs. Zombies has a lot of fans as well and is available on a variety of platforms (which Field Runners is too, at this point). In Field Runners you use actual towers to fight various enemies, and in PLants vs. Zombies you fight oncoming zombies using plants. In Bloons TD, it’s a horde of balloons that you have to fight, using a variety of heavily armed monkeys (originally equipped only with darts, but that’s 4 versions ago).
You place the various monkeys along a path that the balloons will follow and hope you have enough (and have placed them correctly) to pop all balloons before they make it to the end of the path. The balloons increase in “badassness”, where higher level balloons have several lower level balloons inside like some russian doll balloon experiment that got way out of hand. The M.O.A.B (Massive Ornary Air Blimp) is still in the game, but is nothing compared to the newly introduced B.F.B (Brutal Floating Behemoth) which releases 4 M.O.A.Bs if you manage to pop it.
Luckily your own monkeys can also be upgraded. The lowest lewel dart slinging monkey can be upgraded to a catapult monkey, the tac tower can be upgraded to what’s basically a 360 degree flamethrower and so on. The boomerang monkey is one of the most fun ones, as its highest upgrade is a Jedi monkey that throws his lightsaber. The new additions include a airplane monkey that moves around (and can be upgraded to a stealth bomber), a pirate ship monkey, a wizard monkey, an artillery monkey and a banana plant which produces more money for upgrades each round. The Super Monkey is still the highest level monkey but now has an additional upgrade from the last game: the Sun God.
The game offers several levels and several difficulties which gives you more or less money to buy towers for. If you’ve played Bloons TD before you’ll have no trouble making it past round 100 on “easy” on your first try, which will level you all the way to 30 in the game’s level up system and unlock all monkeys and all upgrades (the last of which is the Sun God). The amount of balloons you end up popping is insane- I got an achievement for popping 1 million balloons before I hit round 100 on my first game. Of course increasing the difficulty will make it much much harder to reach that kind of level, but you have to go “easy” at least once just to see 15 Sun Gods going nuts on a continuous stream of B.F.Bs. After around lv 90 though the game will start lagging at times, which is understandable since you have tens of thousands of balloons each round- but it never crashed on me, which is awesome. I also play this on my iPhone 3GS, which has substantially weaker hardware than the iPad or iPhone 4/iTouch 4.
This game is the kind of game that you either love to the point that you won’t get anything else done for hours, or you simply don’t understand the point of. I like Bloons TD better than other tower defense games because of its quirkiness (lightsaber-throwing Jedi monkeys beat zombie-blasting plants any day in my book) but your mileage might vary. I shot a couple of high level (easy mode) gameplay videos that you can check out below. At $2.99 it’s not the cheapest game out there, especially when there’s no iPad specific version and there’s a big sale going on elsewhere, but I still think you should try it. There’s also a Lite version if you want to try it out for free.