Primary Expertise

"Adds Mega Ballista attack, plus all Primary Monkeys in radius get more popping power, ability cooldowns reduced further and tier 1 and 2 upgrades for free."

- In-game descrpition

Primary Expertise is the fifth-tier upgrade of the Monkey Village in Path 1 of Bloons TD 6. It allows all Tier 1 and Tier 2 upgrades for Primary Monkeys within its radius to be purchased for free, increases the pierce bonus to Primary Monkeys to +3 instead of +1, further increases Primary Monkey ability cooldowns from -10% to -20%, itself gains extra influence range (48 to 55), and gives the tower a powerful "Mega Ballista" attack.

The "Mega Ballista" attack fires a magical circular blade which strikes at any range and across barriers, and occasionally adjusts its direction mid-flight to hit more bloons, similar to Glaive Ricochet. Each blade pops 10 layers per hit and pierce through up to 100 regular bloons or 10 MOAB-class Bloons, while it deals 200 damage to Ceramics and MOAB-class Bloons. It is shot every 2.5s.

It costs $21,250 on Easy, $25,000 on Medium, $27,000 on Hard, and $30,000 on Impoppable.

Description
Primary Expertise is a three-towered fortress-like building with a ballista attached to the top of it.

It grants free Tier-1 and Tier-2 upgrades for all Primary Monkeys in range of the Primary Expertise. All Primary Monkeys within its radius also gain +3 pierce instead of +1 pierce, as well as -20% ability cooldowns instead of -10%. Other Primary Training and Primary Mentoring benefits, such as +10% range and +5 range on top, ~+15% projectile speed, are inherited by the Primary Expertise. Besides providing extra bonuses to nearby Primary Monkeys, Primary Expertise can now attack.

Primary Expertise's attack is much different from the High Energy Beacon from BTD5. Instead of a continuous energy beam, the Primary Expertise shoots a magical circular blade every 3.0s that strikes at any range and across barriers, and occasionally adjusts its direction mid-flight to hit more bloons, similar to Glaive Ricochet. Each blade pops 10 layers per hit and pierce through up to 100 regular bloons or 10 MOAB-class Bloons, while it deals 200 damage to Ceramics and MOAB-class Bloons.

Do note that while the attack detects camo, the tower itself does not and so the Advanced Intel upgrade does not detect camo bloons in the Primary Expertise's radius, unless the Primary Expertise has the Radar Scanner crosspath.

Summary
Primary Expertise again further improves its buffs for nearby Primary Monkeys. With the free upgrades portion of this upgrade, this benefit is best combined with the more expensive low tier upgrades for the Bomb Shooter and Glue Gunner. The extra +3 pierce for Primary Monkeys, the even faster ability cooldowns, and itself having a higher influence range define this tower greatly, combining coverage with specialization for both the highest-tier and lowest-tier Primary Monkeys. The mega ballista attack can be useful as a mini cleanup attack.

Tips

 * There is a unique synergy between this upgrade and the Inferno Ring, as it buffs the Inferno Ring's fireball attack to attack 4x as many bloons, due to the fireball initially only have 1 pierce.
 * It is extremely cost effective to combine this tower with MOAB Maulers and Cluster Bombs, as only the third tier upgrade and base cost will cost money. It can also support them by making supporting Glue Gunners and Ice Monkeys cost less.
 * Usually, the better crosspath for Primary Expertise is 5-2-0, for the camo detection via Radar Scanner, as the discount benefits of Path 3 are not very effective in combination with Primary Monkeys. This in no way means 5-0-2 is a bad crosspath, however, as Primary Expertise does not need x-2-x to detect camo and the discount can be useful in situations where discounting more expensive towers nearby are needed.
 * Primary Expertise can be buffed by Alchemist which can be useful if more range is needed. As with all Monkey Villages, adding a second village nearby will also increase its range, though Primary Expertise can also benefit from the other Village's Jungle Drums as well.
 * The cooldown reduction for the primary monkeys' abilities can total up to 40% if combined with Energizer. This can come in handy with strategies that heavily involve Plasma Monkey Fan Club or Perma Charge, for instance.

Trivia

 * The most expensive upgrade that can become free with this tower is the Glue Splatter, saving up to $2,160 on Impoppable for the upgrade alone.
 * The Mega Ballista attack is similar to the High Energy Beacon's lasers from BTD5, as it grants the Monkey Village with an attack, where in other cases it lacks any direct attack.
 * This can solo 4 ZOMGs and 20 DDTs (Tested in Logs on Hard Difficulty Sandbox Mode)
 * In Version 17.0, there was a bug where the Primary Mentoring's +5 range buff and -10% ability cooldown buff did not apply to Primary Expertise. This was fixed in Version 17.1.
 * Primary Expertise can solo on Logs Easy up to Round 92, when placed carefully. This was shown on ISAB's video on One Village Only as shown here.
 * This tower will not benefit from its own Jungle Drums, but placing another 2-0-0 Monkey Village beside it will grant the attack speed boost.
 * Due to its damaging possibility, it is the only one Monkey Village upgrade that can be buffed by Alchemists.