Rainbow Bloon/Strategies

Rainbow Bloons are a major threat earlier on and can break through the player's defenses if they do not use the right towers. The Rainbow Bloon releases two Zebra Bloons, which are immune to both Ice and Bombs and the Rainbow Bloons themselves are very fast, making them hard to pop.

Tips

 * Camo Rainbow Bloons are very dangerous, especially on Round 70, however with a 4-1 Ninja Monkey or even a well-placed 3-1 Ninja Monkey, you can easily destroy it without the need of Road Spikes.
 * 3/x or 4/x Ice Towers are very ineffective and do more harm than good against Regen Rainbow Bloons as when Artic Wind slows them down, Snap Freeze pops the Rainbows, releasing two Zebra Bloons which are immune to ice. Since Snap Freeze cannot harm it, the Zebras will soon regenerate back to Rainbows, only to be popped back into Zebra Bloons again. After a while, the Rainbow Bloons would have multiplied into a very dense amount of bloons and would be very hard to pop when paired with MOABs or BFBs, even with 3/2 Sun Gods or 2/3 Robo Monkeys . If you are considering using Ice Towers, pair them up with a x/3 Monkey Village MIB instead of a Monkey Town to enable the Ice Towers to freeze Zebra and White Bloons. However, with 3-4/2 Ice Towers can make Zebras frozen.

Strategies
Strategy 1:

To pop them, DO NOT use non-missile Bomb Towers, because Rainbow Bloons move very fast and their children are immune to bombs. Try to use projectiles such as darts or if possible; homing projectiles. Despite this, you can still inflict effective explosive damage with Hydra Rocket Pods or the Bloon Area Denial System.

Strategy 2:

Path 1 Ice Towers become redundant against the bloons once the Rainbow Bloon releases its children. Should you want to slow down the Rainbow Bloon, it is better to use a 1-0 Glue Gunner, or if you want to pop the Rainbow Bloon, upgrade to 2/x or higher.

Strategy 3:

To pop the Rainbow Bloon, use fast towers such as Destroyer or Super Monkey.

Strategy 4: 

Sniper Monkeys with the Deadly Precision upgrade can instantly destroy a Rainbow Bloon and its parent, the Ceramic Bloon. In addition, the Point Five Oh Upgrade can reduce a Rainbow Bloon to several Red Bloons. (Eight, to be exact)

Strategy 5:

If you have a weaker defense, you can still use Road Spikes to get rid of any of the Rainbow Bloon's children which leak. Likewise, Spike Factories can eliminate them at around just as well, though you may need more Spike Factories if either the track is short or rushes of Bloons pour in.

Strategy 6:

A Neva-Miss Targeting Monkey Ace is capable of taking down several Rainbow Bloons.

Strategy 7:

A Spectre can pop infinite rainbow Bloons.

Strategy 8:

A 4~5 of 2/2 apprentices are capable of taking down a wave of rainbow bloons

Strategy 9:

Contrary to the info on strategy 1, 4-2 Bloon Impact Bomb Towers are relatively effective against large amounts of Rainbow Bloons. The speed of the rainbow bloon really isn't too much of a concern and aren't too hard to hit with a bomb tower, especially if they are in large hordes. Keep in mind that these bloons are still relatively slower than the pink and Ceramic Bloons so they shouldn't be too much of a hassle. However, do not use them against regen rainbow bloons.

Strategy 10:

Spam tons of 2-3 Dart Monkeys. Rainbow Bloons will get overwhelmed by the amount of darts, resulting them getting popped fast. This strategy is effective against non-Regrow Rushes because that the bloons get popped quickly by the darts. However, if the Dart Monkeys are outnumbered by a huge amount of tightly packed Regrow Rainbows, they will get overwhelmed.

Strategy 11:

3 2-2 super monkey can take down rainbow bloons due to their incrediable range and damage. The help of a 2-2 village can help them attack further, attack faster and help them see camo bloons.

Strategies and Tips (Bloons Pop!)
The Ice Monkey in fact excels at freezing Rainbow Bloons with the Fortified property (and/or the Shielded property) compared to freezing Rainbow Bloons without them. Since it deals 1 damage with every freeze attack, it applies freezing to a bloon after said bloon takes damage, which the White and Zebra Bloons are unaffected by.