Bloons Tower Defense

Bloons Tower Defense is a series of tower defense-style games under the Bloons series produced and created by Ninja Kiwi. It was initially developed as a browser game built upon the Adobe Flash platform, but in later games was made available as an iOS app for the iPhone, iPod touch and iPad as well as for devices operating on Google's Android OS.

Gameplay
The main objective of the game is to prevent balloons, known in the game as Bloons, from reaching the end of the track on the playing field. As implied by the genre, the player has various types of towers at his disposal to defend against the Bloons; including Dart Monkeys, Tack Shooters, Bomb Towers, the powerful Super Monkey, and others introduced in the various versions of the game. The playing area usually consists of a defined track, with one or more entrances and exits for the Bloons. When a Bloon reaches the end of the path, it costs the player lives. When all the player's lives are lost, the game ends.

Bloons
Bloons are the enemies in the game series. They appear at the entrances located on the playing field, and usually follow a definite path on the track until they either reach the exits or are popped. There are many types of Bloons, with the tougher variants containing a number of weaker ones. Some Bloons also have special abilities, or strengths. Depending on the difficulty and version of the game, the player has a certain amount of lives available to them.

Bloons that are under the M.O.A.B. class are larger in size as compared to the normal Bloons. These Bloons takes hundreds of hits to destroy.

Towers
Towers are the main defensive utility in the Bloons TD series. Towers cost money. Each tower has its own unique purpose, power, and use, with some being quite powerful against specific Bloons but unable to target others effectively. Throughout the series the towers have been changed, edited, and many have been added.

Upgrades
Every tower can be upgraded to increase power and other capabilities. In BTD4, each tower has a "secret" upgrade that is extremely powerful. These are expensive and have to be unlocked before use. They are the strongest and final upgrade of each tower. In BTD5, each tower has two upgrade paths of four upgrades each. After the second upgrade in either path, there is a split-off point. Once the third upgrade is purchased on one path, upgrading on the other path, above the second upgrade, is disabled. Also, in BTD5, there are Special Agents Pros, which are unlocked by placing a specific Special Agents a number of times which improves the Special Agent's capabilities.

Premium upgrades
Premium upgrades was first introduced in BTD4. NK coins, which is the Ninja Kiwi Credit, are required to purchase them, unless the user has purchased BTD5 Deluxe Version. NK coins cost real money. Some of the premium upgrades are Dreadnought, Double Ranga, and Double Cash. These upgrades can be activated and deactivated through the premium upgrades panel. Some BTD4 premium upgrades like Frag Bombs have been made into BTD5 regular upgrades. Some premium upgrades cannot be used in Daily Challenges or Special Missions. Others can be purchased more than once, like Extra Cash, More Lives, and various options for extra Monkey Money. Bloon Tower Defense 5 added Monkey Money that can be earned through completing levels or by purchasing. On the Kongregate version, Kreds are used instead of NK coins.

Money
A form of currency in the game, known simply as money, is earned by popping Bloons. One money is earned for each layer popped and some bonus money is earned at the end of each round. In Bloons TD 4, a new tower, the Banana Farm, was added which gives extra money. An alternate currency introduced in BTD5, known as Monkey Money, is used to buy Special Agents and buildings. Special Agents help out in a game along with the normal towers.

Series
There are currently five games in the Bloons Tower Defense series, in addition to various other add-on packs such as "Bloons Tower Defense 4 Expansion". There are also versions of the game which were ported to other platforms, including iOS.

The series was retitled from Bloons Tower Defense to Bloons TD in January 2010 due to infringement on the TowerDefense trademark owned by Com2uS.

Bloons TD
Bloons TD is the first game in the BTD series, released in late 2007. Towers are high priced in Bloons TD, but as more towers are added the price is lowered. It is limited to six Bloon types, red, blue, green, yellow, black, and white. All Bloons with the exception of Red have a number of smaller Bloons inside of them, while others (namely Black and White) had certain invulnerabilities such as, being popped by explosions and being frozen. There are five towers to choose from to pop the Bloons; including the Dart Tower, Tack Tower, Ice Tower, Bomb Tower, and the Super Monkey. Players are provided 40 lives to beat 50 levels; unlike later versions of the game, there are no separate difficulty levels and there is only one track to choose from. The Super Monkey is the most expensive tower in the game, costing four thousand coins. In later versions, the price of towers were lowered.

Bloons TD 2
Bloons TD 2 was released in early 2008. It added new towers and some were renamed.

Bloons TD 3


Bloons TD 3 was released in 2008, after Bloons TD 2. It added ceramic Bloons and M.O.A.B.s (Massive Ornary Air Blimp), both of which are difficult to pop due to their ability to endure multiple shots from the player's towers. There were now four tracks available the first time the game is played, but four more can be unlocked by playing it on Ninja Kiwi. Bloons TD 3 added another 3 towers, including the Monkey Beacon, which strengthens nearby towers, the Spike-O-Pult, which flings one heavy spiked ball that can pop multiple bloons, and the Super Monkey Storm, which wipes out every single bloon on the screen except for M.O.A.B.s and is unlocked by the Monkey Beacon. There are also four upgrades available for most towers, instead of the two from the previous games. A new free-play mode was introduced if level 50 is beaten in each course. The cost of the Super Monkey tower was brought down once more to 3,400 coins.

A version for iOS called Bloons TD was made available on October 2, 2009 from the iTunes App Store. On January 26, 2010 a free, feature-restricted version was released called Bloons TD Lite. Another version of the game, simply titled Bloons TD, was released for DSiWare in 2011.

Bloons TD 4


Bloons TD 4 was released in October 2009. The gameplay underwent fairly major changes, including the ability to save the current game (which requires a MochiGames account) and the introduction of an unlocking-based system; which made it so that towers, upgrades, and the new Sandbox and Apocalypse modes were unlocked over time. The player can now start with 100 to 200 lives depending on the difficulty chosen. Towers now have one upgrade path with four upgrades, instead of the previous split paths. The Spike-O-Pult was removed but changed into the 3rd upgrade for the Dart Monkey. The Juggernaut upgrade was also removed from BTD3. New towers included the Spike Factory, Monkey Ace, Monkey Buccaneer, Dartling Gun, Monkey Apprentice, Banana Farm, Mortar Tower and, Glue Gunner. Monkey Glue was removed with the arrival of the Glue Gunner. The Dartling Gun tower was the first tower to be controlled by movement of the mouse, in which the player must move the curser to the position the Dartling Gun must aim to shoot. The Super Monkey also was given a new upgrade to players who reached career rank 30. A blimp called B.F.B. (Brutal Flying Behemoth),and new bloons (pink, camo,  and zebra) were introduced. A B.F.B. contains four M.O.A.B.s and takes a long time to defeat. A leveling system was also introduced, which directly corresponds to the unlocking system. The more Bloons the player pops over the course of his game "career", the higher his level climbs; and hence the more features become available for use. The player's current level status is kept persistently even if the player closes his browser, which improves aspects of long-term gameplay. In the new Sandbox mode (unlocked at rank 26), the player can practice strategy and tower placement with virtually unlimited money and lives (1,000,000 and 100,000 respectively). In Apopalypse mode (unlocked at rank 31), there are no breaks between levels. Bloons come in constant, unending waves.

The game graphics were also completely revamped, with the towers looking more polished and 3-D.

Bloons TD 4 introduced seven new tower types, with each receiving additional upgrades including a final, powerful (and expensive) super-upgrade. New Bloons were also added, as well as additional towers, and player options. Some levels received special challenges.

A version for iOS called Bloons TD 4 was released via iTunes App Store on December 7, 2010. On January 19, 2011 a free, feature-restricted version was released called Bloons TD 4 Lite. An iPad version called Bloons TD 4 HD was then released on March 31, 2011. This was followed by the release of a free iPad version called Bloons TD 4 HD Lite on April 28, 2011. BTD4 for Android arrived in the Play Store in 2011. A version of the game was also released as a DSiWare game later in 2012.

Bloons TD 4 Expansion
The expansion for Bloons TD4 adds 4 tracks: the Sandy Spiral Track, the Subterranean Sewers, the Secret of the Monkey Temple, and the Triangle of Insanity. This expansion also includes a game mode, Deflation Mode, in which one starts at round 21 with $50,000 and does not earn any more money during game play, with banana farms disabled. The expansion also has tower specialties unlocked after beating different tracks on different difficulty levels. These allow some towers and their upgrades to be cheaper while all the other towers and their upgrades are made more expensive.

Bloons TD 5
Bloons TD 5 was released on December 14, 2011 for all Ninja Kiwi accounts. On December 15, 2011, Bloons Tower Defence 5 was released worldwide, with revamped graphics, new upgrades and tracks (including the Juggernaut upgrade from BTD3), 400 rounds in every difficulty level (excluding sandbox) in all tracks, and three new towers; the Ninja Monkey, Sniper Monkey, and Monkey Village, an enhanced version of the Monkey Beacon in older Bloons installments. BTD5 includes a new M.O.A.B. Class Bloon known as the Z.O.M.G. (Zeppelin Of Mighty Gargantuaness), which contains four B.F.Bs, which each contain four M.O.A.Bs each. Also new is a type of Bloons called regens, which can grow back their layers if not popped fast enough. The game released eight new tracks with moving parts, 16 tower types, new Camo and Regenerating Bloons, as well as two upgrade paths for each tower.

It was announced on November 2, 2012 that Bloons TD 5 would be coming to iOS sometime in November. On November 15, 2012, BTD 5 was released on iOS worldwide.

Bloons TD 5 Deluxe
On May 31, 2012, Ninja Kiwi revealed that a new and improved version of BTD5 was underway. Titled Bloons TD 5 Deluxe, this is a special edition to the Bloon series, this time being a digital-copy version (Running on Adobe Air) rather than the standard flash version from previous installments. Now revamped with a higher resolution, BTD5D introduces 10 new tracks, some veteran favorites from BTD4, new Special Missions, Special Agents and even two new never-before-seen towers, Monkey Engineer and Bloonchipper, in addition to the current content available on the flash version. Monkey Money is also highly integrated, making it easier to achieve and can even be used to purchase Premium upgrades. However, the game doesn't use all the current progress made by an NK account (such as Awesome Points), so players starts from Rank 1, but all data saved on the flash version is not erased. BTD5D was up for preorder for $20 (with 100 NK coins for the player's BTD5 account included) for what was originally a $25 game; the price has now dropped to $15.

Bloons TD 5 mobile
On November 15, Ninja Kiwi released Bloons TD5 for iPhones and iPods with a new tower (Heli Pilot), a new special agent (Radadactyl), an inclusion of the Monkey Engineer and Bloonchipper from the Deluxe version of Bloons TD 5 (In updates), 4 new tracks, and a "Monkey Lab" where players can buy upgrades that help general game play. The iPad version of the game was released December 1, 2012. It is currently priced at $3.00. The Android version of the game with the same feature set was released February 5, 2013, for $2.99 on Google Play.

Reception
IGN editor Daemon Hatfield stated that Bloons Tower Defense 3 succeeds in standing out in this crowded genre by having the core game mechanics right and adding their own individual twist. GameZebo editor Jim Squires gave Bloons Tower Defense 4 a 3.5/5 rating, praising it on its "Well designed maps and towers" and for having "Tons of content"; although it was criticised for not "bringing anything new to the genre." GamePro editor Ryan Rigney gave Bloons Tower Defense 4 a 2/5 rating, stating that it has "The same Bloons tower defense gameplay" as the previous titles, and "the screen eventually gets so hectic that it's no longer fun to play". However, Wired called the game "pop culture at its best".