Support Monkeys

Support Monkeys are the fourth and final category of towers in BTD6. They are unlocked at Level 18, after all Magic Monkeys are unlocked. The common traits shared by all Support Monkeys is that they are all primarily designed to form a supporting role for the main defense. Support Monkeys are identified by a light orange background, resembling the construction theme of Support Monkeys.

There are 4 Support Monkeys in the game:

Support Monkeys affect the sacrifice categories for Sun Temple and True Sun God (and by extent, Avatar of the Vengeful Monkey too). Support Monkeys currently have no special class-exclusive benefits via towers, although Banana Central can improve all income for all Banana Research Facilities on screen. Support Monkeys can also be placed on the yellow emblem on the map Encrypted, although only Spike Factory and Engineer Monkey are small enough to fit there. There is currently no "Support Monkeys Only" game mode.

Introduction to Support Monkeys

 * Banana Farm: Banana Farms cannot directly harm bloons, but they produce bananas that reward the player with a source of bonus income. They consume the highest amount of footprint compared to other tower types, but they become more valuable the earlier they are bought, extrapolating a high profit margin if enough farming is performed. Banana Farms can be upgraded to further improve income generation in many different ways.
 * Spike Factory: The Spike Factory is a spike production machine, regularly producing spikes towards nearby track. Their main role is to act as a protection at nearby exits, stopping bloons including Camo Bloons from leaking through the exit. Spike Factories regularly stockpile spikes towards the exit, gradually creating a stronger barrier against incoming bloons. Spikes do not last indefinitely, however, but the Spike Factory can be upgraded to produce stronger spike piles, generate spikes faster, or improve the quality of each spike and its production.
 * Monkey Village: Towers within the range of a Monkey Village will gain extra range, among other buffs with extra upgrades. The Monkey Village has a very limited way to directly affect bloons, and relies primarily on supporting nearby towers with various types of supports to make up for its limited offense. It can be upgraded to apply new and improved buffs that improve general stats of towers or allow them to affect different types of bloons. Certain upgrades allow the Monkey Village to directly harm bloons in a limited way (such as Grow Blocker, which prevents Regrow Bloons from healing while in range of the Village, and Primary Expertise upgrade provides the Village with a powerful seeking attack, allowing it to directly damage Bloons.)
 * Engineer Monkey: The only true monkey of its kind, the Engineer Monkey is a skillful craftsmonkey who can utilize various tools and create various contraptions to support the defense. The Engineer Monkey's earlier upgrades have a decent amount of pierce and range potential, as well as possessing a way to slow the progress of weaker types of bloons. Later upgrades allow the Engineer Monkey to become a stronger support role at DPS, gain buffing potential, or do instakills. While not able to directly spot camo bloons regardless of upgrades, the Engineer Monkey's Cleansing Foam can strip off camo from any bloon touching them.

Summary
Support Monkeys provide primarily supporting roles that other defenses may lack. Many of these are passive supports that either improve existing towers or generate income, but some of these towers form supporting DPS, those being the Spike Factory and Engineer Monkey. When combined with other classes, towers from the Support Monkeys class can help address weaknesses that other tower classes tend to miss out on.

Tips

 * It is not a good idea to invest too much money on support towers (except the Engineer Monkey) early game as you could be easily overwhelmed by the bloons because of the limited starting cash.
 * Many towers outside of the Support category can serve supportive roles with certain upgrades, such as removal of bloon properties (Signal Flare, Heart of Oak), generation of cash (Merchantman, Rubber to Gold), buffing of other towers (Berserker Brew, Energizer), impeding bloon progress (Bloon Sabotage, Druid of the Storm, Glue Gunner, Ice Monkey), making bloons take more damage (Glue Strike, Embrittlement) or other helpful purposes (Support Chinook).

Trivia

 * Engineer Monkey and Spike Factory are primarily attack-focused despite their category, but Engineer's Cleansing Foam and boost abilities (Overclock and Ultraboost) definitely serve a supportive role.
 * It could be said that Spike Factory's support role is to be used as a cleanup tower, especially against bloons close to the exit, as this is the primary design of the Spike Factory. Engineer's Bloon Trap and XXXL Trap also serve this purpose.
 * Likewise, Engineer Monkey could be a support role for supporting the early-game, particularly with its variety of effective early-game options for upgrades up to Tier 3.
 * Benjamin can be considered the Hero equivalent of a support monkey, as his role is exclusively to generate cash (like a Banana Farm) and boost other monkeys' attack speed (like a Village) without any direct damage ability of his own.
 * Other heroes that can serve a supportive role are Striker Jones (boosts to Bomb Shooters and Mortar Monkeys), Obyn Greenfoot (boosts to Druids and Magic Monkeys), Pat Fusty ("Rallying Roar" damage buff ability), Admiral Brickell ("Naval Tactics" water tower buff ability), Gwendolin (periodic damage buff & Lead-popping ability), and Etienne (global Camo detection).
 * Arguably, Support Towers in general have an urban or construction-based theme.
 * The Engineer Monkey is currently the only tower in the Support category that is a monkey.
 * While the other 3 tower categories (excluding Heroes) have exclusive gamemodes, Support does not.
 * If there is a Support Monkeys Only mode, it will likely use the Impoppable Difficulty, going with the pattern of difficulties used by the game modes previously mentioned.
 * Playing with only Support Monkeys anyways contributes to the achievement Unsung Monkeys.
 * Until the Monkey Engineer Paragon is released to the general public, Support Monkeys will be the only Tower Class to not have any Paragons.