- The boss will move in a straight line in a random direction, passing over blocks and eliminating bombs in its path. Bomberman will take damage if he makes contact with it.
- Somewhere along the way, the boss will come to a stop and shoot a fireball out of each of its four cannons. The fireballs will land, one at a time, in an open row or column that Bomberman is currently occupying. Each fireball falls slowly, with a shadow indicating its landing spot, and explodes with a blast that extends to the edges of the arena. After all four fireballs have been released, Breast Fire will pause before moving again.
The boss will typically damage itself with its own explosions, and can actually be defeated without a single bomb having been set by the player. Fireballs can even be "guided" to explode on a row or column that the boss occupies.