The Apopalypse Bloon is the Boss of the Hard difficulty in BTD6 above advanced track difficulty (Expert, Extreme, Nearly Impossible). It takes the appearance of the icon of the Apopalypse Mode in BTD5 and is only slightly bigger than a normal Bloon. It moves slightly faster than a red bloon, but slower than a Blue Bloon. It only appears once in the game at round 100. It takes 20000 hits to pop, doesn't spawn any children, and has these special abilities that randomly trigger at times:
- Spawn Ceramic Bloons: It'll fly around the screen very quickly when spawning 10 Ceramic Bloons per second for 10 seconds. After that, it 'll return to its old position.
- Spawn MOABs: It'll fly around the screen very quickly when spawning 1 MOAB per second for 10 seconds. After that, it 'll return to its old position.
- Apopalypse Charge: It'll charge up for about 3 seconds then fly to the finish at hypersonic speed. If it's hit 200 times before it reaches the finish it'll return to its old position.
- Apopalypse Strike: Summon lightning that hits all of your towers, nullifying them for 5 seconds and dealing 8HP damage.
- Death Curse: Curse a specific tower, dealing 60HP damage. Can break
- Bones: Bones fall from the sky causing damage to towers
- Although it's a Boss and takes many hits to be popped, it's NOT a MOAB-Class Bloon and only have traits of a Ceramic Bloon.
- The BGM of its boss fight is a version of Gaussian Blur 3