Crosspathing/Heli Pilot

In Bloons TD 6, it is important to choose the best crosspathing for a specific tower in order to receive the best benefits out of that tower type. Towers have special roles to play for each stage of the game. The Heli Pilot in its core is to be fully mobile, controllable to how the player directs it to be.

Introduction
Heli Pilot is the second most expensive base tower in the game, second to the Super Monkey. It glides in the air and it is able to ignore line of sight. It goes where ever you last put your finger/mouse on the screen. This allows it go wherever you need it to go. At its base, the Heli pilot shoots two darts, each with a pierce of 4 and damage of 1. Path 1 focuses on offense. Path 2 centers around support. Path 3 is all about defensive measures, with M.O.A.B Shove as an example. Crosspathing isn't the most important for Heli Pilot although it can matter what crosspaths you do. Note that if you want to buff the Heli Pilot, you put your support towers at the Heli Pad and not at the Heli itself.

Tier 2 and below



 * 0-0-0: Solid attack speed, pierce, and the ability to move anywhere on the screen makes a base Heli Pilot, not that bad as an early, albeit expensive option.
 * 1-0-0: This doubles its popping power, as it adds 2 more dispensers which makes it quite good for saving up for more expensive options.
 * 0-1-0: Allows the Heli Pilot to move faster onto the screen. Even though it sounds useful, its not necessary since its rarely a problem with such slow bloons. It's also redundant since it has the option to be locked in place, which makes faster movement useless.
 * 0-0-1: On the rare case where you need to snipe bloons from afar more easily, you go this crosspath.
 * 1-1-0: Not a great crosspath because on higher tiers, this crosspath can hurt, more than help, a defense.
 * 1-0-1: Often a stepping stone for 1-0-2, as all Faster Darts does is increase projectile speed.
 * 0-1-1: Usually a stepping stone for 0-2-3. In itself, it does little to nothing due to only affecting the projectile speed of darts.
 * 2-0-0: This infamous upgrade is known for making the players defense worse, if they are going for Path 1 Tier 3 or more. Though, if you can't micro manage the Heli effectively, than its better to use the pursuit option as it follows the bloons pretty accurately.
 * 0-2-0: The cheapest option for Camo detection for the Heli.
 * 0-0-2: This increases the attack speed of the Heli.
 * 2-1-0: A good crosspath on paper, but it loses out on obtaining extra attack speed via Path 3.
 * 2-2-0: The reason why this crosspath is atrocious, (not just this specific crosspath, but any x-x-0 crosspath) is because the paths that are affected by this crosspath, (that is, Top path and Middle Path) don't need each other. Top path needs Bottom Path's increase in DPS, while Middle doesn't even need any crosspath to begin with since it fills a support role that isn't supposed to good a dealing good DPS.
 * 1-2-0: It has the same reasoning as 2-2-0 but without the automatic pursuiting.
 * 0-2-1: A 0-1-1 that sees camo bloons.
 * 1-0-2: The better crosspath as it maximize DPS for its higher tiers.
 * 2-0-2: A 1-0-2 with the option to follow the bloons.
 * 0-1-2: Usually stepping stone for 0-2-3. In itself, it adds faster rate of shooting darts.
 * 0-2-2: A 0-1-2 that sees camo bloons.

Razor Rotors

 * 3-0-0: This makes the rotors on the Heli pop bloons which can pop bloons, including leads. Crosspathing will only affect the main Heli's attacks, with exception of 3-2-0 for countering Camo Leads. Usually a good stepping stone for its 4th Tier upgrade.
 * 3-1-0: Directly affects Pursuit by flying faster. Normally a stepping stone for 3-2-0.
 * 3-2-0: Not the preferred upgrade since DPS is the main niche of this upgrade path and trading that for faster travel speed and Camo detection makes it harder for Razor Rotors to stay behind the bloons where it can get the most value and camo detection that can be given through external means. Tends to be used mostly as a Camo Lead counter.
 * 3-0-1: This only makes the darts fly faster which only matters in very specific circumstances.
 * 3-0-2: The preferred crosspathing as this will significantly increase the DPS for the Higher Tier upgrades for this path.

Apache Dartship

 * 4-0-0: Gains powerful machine gun attack and quad missiles. Crosspathing gives it its optimal damage potential for whatever circumstances it may need to deal with. Only Tier 2 crosspathing is truly worth for Apache.
 * 4-1-0: Allows the Apache Dartship to fly faster. Not worth paying for this over Faster Firing, which increases its DPS.
 * 4-2-0: Gains camo detection, but is often redundant in practical games, given that it is both unable to damage DDTs sufficiently (note that its rotor can damage DDTs but deals negligible DDT damage). Can be used to deal with grouped camo bloons, but adding a Radar Scanner or any decamo sources is sufficient.
 * 4-0-1: Faster projectile speed doesn't affect the Apache much, since the main use of the Apache Dartship is to have the Heli be up and close to incoming bloons.
 * 4-0-2: The better crosspath for the Apache Dartship, as it allows it to attack 25% faster and maximize its varied damage output.

Apache Prime

 * 5-0-0: Apache Prime proves an effective counter to Super Ceramic Bloons and most blimps encasing them when given adequate support. There is literally no reason to not crosspath an Apache Prime, however, as most of its true value is hidden beneath crosspathing benefits.
 * 5-1-0: Allows the Apache Prime to fly faster. Not worth paying for this over Faster Firing, which increases its DPS.
 * 5-2-0: Redundant in practical games, because the MIB is necessary to brute-force through Apache Prime's glaringly obvious weaknesses to DDTs and Purple Bloons. Since MIB already comes with Radar Scanner, which grants nearby towers with camo detection, including Heli Pilots. 5-2-0 is limited mostly on custom challenges.
 * 5-0-1: Faster projectile speed doesn't affect the Apache much, since the main use of the Apache Prime is to have the Heli be up and close to incoming bloons.
 * 5-0-2: The better crosspath for the Apache Prime, as it allows it to attack 25% faster and maximize its varied damage output.

Downdraft

 * 0-3-0: Downdraft allows the Heli Pilot to blowback each bloon at a quick rate. Crosspathing is not required because of the reliability of Downdraft's blowback effects compared to alternate options, but a crosspath can be added to support different needs.
 * 1-3-0: Quad Darts does nothing to boost the blowback effects, but Quad Darts does provide a valuable source of extra DPS.
 * 2-3-0: Allows blowback positioning to be adjusted automatically via the Pursuit target priority
 * 0-3-1: This crosspath has no use outside of trying to save up for 0-3-2 Downdraft, as this simply speaking only improves projectile speed of the main dart.
 * 0-3-2: The better crosspath for manually controlled blowback. Also is the better option if seeking to upgrade further to Special Poperations.

Support Chinook

 * 0-4-0: Chinook's main power is its abilities. Crosspathing should be based mostly on its previous upgrade, Downdraft, as well as for Special Poperations.
 * 1-4-0: As with Downdraft, Quad Darts does nothing to boost the blowback effects, but Quad Darts does provide a valuable source of extra DPS.
 * 2-4-0: For Chinook, it may take longer or shorter to reach the destinated tower to pickup and reposition. Otherwise, this is mostly for the Downdraft benefit.
 * 0-4-1: This crosspath has no use outside of trying to save up for 0-4-2 Chinook's Downdraft effects, as this simply speaking only improves projectile speed of the main dart.
 * 0-4-2: The better crosspath for manually controlled blowback. Also is the better option if seeking to upgrade further to Special Poperations.

Special Poperations

 * 0-5-0: Special Poperations adds the option to drop a Marine wielding a dart-shooting machine gun. Crosspathing is worth adding, particularly 0-5-2 but requires micromanagement to maximize, while 2-5-0 is for convenience purposes.
 * 1-5-0: Useless of a crosspath due to the fact that it does no effect to the dropped Marine. The extra darts for the Heli shadow in comparison.
 * 2-5-0: More convenient for a much reduced micro when set on Pursuit, allowing the Marines to be dropped as close to the main action as possible without manually changing the Heli Pilot's position.
 * 0-5-1: Useless of a crosspath because darts only move faster, not attack faster.
 * 0-5-2: The better crosspath for Special Poperations due to the Faster Firing crosspath buffing the attack speed of the dropped Marine too.

MOAB Shove

 * 0-0-3: MOAB Shove allows the Heli Pilot to apply shove-based knockback MOAB-class bloons upon collision with their hitboxes. A single MOAB Shove can only knockback one MOAB-class bloon at a time, which can be problematic in later rounds where there are even more MOAB-class bloons.
 * 1-0-3: This does nothing to the MOAB Shove effect, but the Quad Darts attack gives more damage for the main Heli.
 * 2-0-3: Pursuit targeting allows the MOAB Shove to follow the first bloon on screen, often the leading MOAB-class bloons.
 * 0-1-3: The shoving effect becomes considerably stronger, meaning it can slow down MOAB-class better.
 * 0-2-3: Innate camo detection allows it to target DDTs without need of Radar Scanner or similar camo countermeasures. Plus, it comes with the stronger shove effect via 0-1-3.

Comanche Defense

 * 0-0-4: The bulk of the Comanche Defense's power is through the mini-Comanches. Any crosspath benefit except Pursuit affects mini-Comanches, as mini-Comanches always already go on Pursuit by default. Crosspath depending on needs of the defense, preferably Path 1 with external support for the higher DPS.
 * 1-0-4: Using this crosspath boosts the mini-Comanches' dart count too, for even more DPS. This is generally the better crosspath for Comanche Defense.
 * 2-0-4: Normally redundant unless needing an automatic way for the main Heli to apply MOAB Shove effects on blimps. Note that the mini-Comanches automatically go on Pursuit targeting no matter the crosspath.
 * 0-1-4: Increases flight speed of all Comanches, main and mini. Also increases Shove effect against blimps with main Comanche. Not a strong crosspath because 1-0-4 is more desirable for the better DPS.
 * 0-2-4: Internal camo for the Comanches, main and mini. External camo plus extra darts is more desirable because Comanche Defense is all about extra DPS, not basic blimp support.

Comanche Commander

 * 0-0-5: Comanche Commander lets the mini-Comanches become permanent, and all its darts deal +1 damage. When bought, the Comanche Commander automatically summons mini-Comanches right underneath the main helicopter. Crosspathing is very useful here, particularly Path 1 for utilizing the better DPS. Path 2 is subpar in comparison.
 * 1-0-5: Using this crosspath boosts the mini-Comanches' dart count too, for even more DPS. This is generally the better crosspath for Comanche Commander. The mini-Comanches are also permanent and all attacks gain +1 damage, and so the extra DPS from this crosspath is even more important.
 * 2-0-5: Similar principles to 2-0-4 Comanche Defense.
 * 0-1-5: Increased flight speed isn't very useful for Comanche Commander because its mini-Comanches last forever and always use Pursuit targeting.
 * 0-2-5: External camo is more favorable here than to get internal camo detection, especially considering its price.

Strategy
In the same way Monkey Ace crosspath comes down to whether the player wants Camo Detection via Spy Plane or extra damage output from the other crosspaths, Heli Pilot Crosspath also comes down whether the player wants Camo Detection via IFR and the extra damage output form the other paths.