Recursive Cluster

"Every second shot the cluster bombs send out more cluster bombs for even more destruction."

- BTD6 Description

Recursive Cluster is the Tier 4 upgrade of Path 3 for the Bomb Shooter in Bloons TD 6. It allows the Bomb Shooter's cluster bombs to shoot out more cluster bombs every second shot. Visually on every second shot, all 8 cluster bombs will explode into 8 more cluster bombs, totaling to 64 bombs. But in reality the tertiary explosions are just 8 larger explosions exploding 0.45s later. Every bomb and its clusters from this upgrade can also pop Black Bloon properties.

Recursive bombs work much differently from normal cluster bombs. The primary recursive bomb explosion has a 12 blast radius with 18 pierce. Afterwards, the 8 secondary recursive bomb explosion explode, each having 15 blast radius and 10 pierce. And after 0.45s, 8 tertiary explosions will become produced, each with 34 blast radius and 60 pierce. Crosspathing with Bigger Bombs increases pierce of tertiary explosions by +36 (96 pierce), +6 for secondary explosions, but none for the main explosion, strangely. Heavy Bombs increases the pierce amounts to from +36 to +60 (120 pierce) for tertiary explosions and another +10 pierce for secondary explosions, alongside +1 damage for all explosions. Blast radius for primary and secondary explosions increases by +50% with Path 1 upgrades, or from 34 to 37.5 for tertiary explosions.

It costs $2,380 on Easy, $2,800 on Medium, $3,025 on Hard, and $3,360 on Impoppable.

Tower Prices

 * Updated as of Version 29.4

Summary
The Recursive Cluster is extremely effective at cleaning up regular bloons, and also dealing large amounts of damage to MOAB-class bloons with its numerous explosions. Even just one or two Recursive Clusters can wipe out large amounts of bloons with ease.

When picking the best Recursive Cluster crosspath, Path 1 is generally preferred over Path 2. Despite Path 2's Faster Reload and Missile Launcher upgrades allowing the Recursive Cluster to shoot much faster, and therefore shoot recursive cluster bombs more often, Path 1's Bigger Bombs and especially Heavy Bombs increase the Recursive Cluster's popping power much more, by increasing explosion radius, pierce, and increasing damage. However, if using Berserker Brew or its successors, the DPS of the path 2 crosspath is higher due to damage no longer being a big enough of a boost compared to attack speed, though blast radius is unaccounted for.

If planning to spam Recursive Clusters, using Striker Jones as the chosen hero is one of the best options for optimizing the Recursive Cluster spam. Increased attack speed and pierce are one of many vital assets for Recursive Clusters. In addition, Level 20 Striker Jones maximizes the power of Recursives by doubling their damage. Primary Mentoring also helps save money for the more expensive Bomb upgrades as well as give an appreciable boost at direct range.

Tips

 * A 2-0-4 Recursive Cluster is generally preferred over a 0-2-4 Recursive Cluster as the Path 1 upgrades increase its overall popping power much more. 0-2-4 Recursive Cluster works well with buffs such as Berserker Brew, synergizing damage and attack speed stats better at the cost of explosive coverage.
 * In general, Recursive Cluster can wipe out a lot of bloons at once with ease. Even without Bigger Bombs or Heavy Bombs, it can deal multiple layers of damage with its multiple cluster bombs.
 * Recursive Cluster does a fair job at dealing high damage to both bloons and MOAB-class, but it is quite expensive for what it does compared to other options. However, Recursive Cluster does its job well at creating widespread high-pierce grouped damage.
 * However, if using Striker Jones, Recursive Cluster is actually an excellent option, as he provides global bonus attack speed.
 * A 2-0-4 Recursive Cluster can make Round 63 a lot less difficult, especially with other supporting towers.

Trivia

 * The description used to be "Every 3 shots the cluster bombs send out more cluster bombs for even more destruction." but it has changed in Version 4.0 to fit the new buff of more frequent recursive cluster bombs.
 * Interestingly, the image of its Insta Monkey appeared to have 6 muzzles, though it only has 1 in game, implying the upgrade has gone through a visual change in development.
 * This is no longer true in later versions, particularly Version 7.0+.