Fireball

Fireball is an upgrade for the Monkey Apprentice. It appears in Bloons Tower Defense 4 and Bloons Tower Defense 5.

Bloons Tower Defense 4
Fireball is the second upgrade for the Monkey Apprentice. It is used as a projectile.

Bloons Tower Defense 5
Fireball is the first upgrade on path 2 and is also a projectile used by the Monkey Apprentice in BTD5. It costs 255(easy) 300(medium) 325(hard)

Trivia

 * In BTD5, the fireball looks like the Dreadnaught Premium Upgrade when its launched by the Monkey Buccaneer in BTD5 but on BTD4 is a big fireball.