Dreadbloon: Armored Behemoth

Dreadbloon: Armored Behemoth is an Event-only MOAB-Class Bloon found in the Dreadbloon event in Bloons Monkey City. In the battle, Dreadbloon's health is displayed on the top. You do not receive a tile for completing the level. Upon popping Dreadbloon, you will see Dreadbloon saying "Watch your back!" and receive the relative tier of CT Milestone worth in rewards. If you fail to pop Dreadbloon, you will receive a message with the normal "DEFEAT!" showing, and text that says: "...But the Boss is damaged. Chase it down and try again!"

The Dreadbloon appears in a cave level with multiple folds on the track.

Dreadbloon also appears in BTD5 Mobile and Bloons Super Monkey 2 Mobile. The Dreadbloon is the fourth boss in Helium Heights. It appears in the fourth chapter Digging Deep On Level 75.

Properties & Abilities

 * The boss has the ability to 'grow' a yellow stone layer. It regains its stone armor for each boss HP level, regaining its shell a total of 4 times, including when it spawns. This stone armor can be hit by any type of attack. Despite its appearance as well as the sound effects given from damaging the stone layer, it does not have Ceramic properties, which is why Juggernauts and Spiked Balls do not do extra damage to them.
 * When not under the stone layer, Dreadbloon has the ability of a lead bloon, and therefore is immune to sharp projectiles. Dreadbloon can be damaged by the engineer's lead popping foam, but only pops once per foam clump.
 * Boss Bane does extra damage to its stone armor.
 * Dreadbloon does not award cash for inflicting damage while the stone armor is active, as this is not part of the bloon. The same goes for ceramic bloons.
 * This boss does not spawn any children bloons.
 * In Bloons Super Monkey 2 Mobile, Dreadbloon also has the ability to levitate rocks around him and use it as a shield. Similar to his ability in BTD5 mobile and BMC.

Boss + Shield Health
Dreadbloon's health for any level past level 19 can be determined using the equation below, where "x" is the level to be accounted for (the equation also takes Dreadbloon's shield ramping into account):

(1000x² - 24500x + 181500) + (4 * 10x²), x ≥ 20 or 500(2x² - 49x + 363) + 40x²

Trivia

 * When the boss is defeated, all other bloons will be dazed and popped that indicates that the mission is completed. This is also true for other bosses.
 * In higher levels (10+), the boss will regain a minor amount of its stone armor even when its health does not reach the skull milestone bars, which gets higher as you deplete more skulls (from a measly 10% of its shield to 50% at the last skull).
 * The Super Monkey's Laser Vision does not do damage to the boss due to its lead properties, but the laser can pass through the boss, although a normal Lead Bloon cannot be pierced by lasers.
 * It can be thought that the ceramic-like layer on the outside of this boss bloon is actually made of dirt or clay dug up from the ground, as the pre-battle image shows the armored behemoth drilling out from the ground, surrounded by dirt or the like. Also, Dreadbloon stops each time it regains its clay armor, when it is possibly digging dirt up from the ground and covering itself in it. During this time, the boss cannot take damage, so assassin spam will not work on the boss while it's regenerating. BUG: If the boss is frozen (via Boss Chill) while it is regenerating, the boss will start moving again once it's finished.
 * Due to the boss's low HP at Rounds 1, 2, 3, and 4, Boss Blast can instantly kill Dreadbloon at those levels and leave Dreadbloon with 100 health at Round 5.
 * In the Mobile version, the Absolute Zero ability can slow Dreadbloon down. Additionally, its size is not enough to reach spikes on parallel path portions.
 * A single MOAB Assassin Ability is just enough to destroy non-clay-armored Dreadbloon Levels 1 to 3.
 * You must destroy Dreadbloon to win level 75 in Bloons Super Monkey 2 mobile.
 * MOAB Maulers can do extra damage to the clay layer.
 * In November 2018, Dreadbloon no longer roars when defeated, instead simply making blast sounds until it explodes.

Boss Escapes
If the player loses, the player must pay some city cash to try again. The first attempt is free. The nth attempt costs (Dreadbloon Level) x 100 x (n-1) x (n-1). For example, your 5th attempt at level 3 Dreadbloon would cost 300x(5-1)x(5-1) or simply 4800. The player has 1 hour to defeat the boss otherwise the boss will flee and hide but it will return with full health after defeating another Bloon Beacon tile.