Instructions
Collect firepower up to level 2. Set down one to three bombs in strategic locations to capture the three robots between the bombs. When the bombs blow the robot boss will die.
Collect firepower from level 2 to level 8. Set a bomb one square from the wall and parallel to this bosses middle leg. Set the bomb to blow right after he releases his firebombs.
Avoid the attempt by the third boss to pop out of the ground under you and dodge the pink lightning he throws. Lay bombs in his path as he moves around. Each bomb inflicts some damage and will kill him.
Avoid the two bombs the fourth boss throws at you. Place a bomb right next to him on the side he didn't throw the bombs from. Repeat the process until the bombs kill him.
Get level 2 to level 8 firepower for your bombs. Set bombs in the path of the fifth boss and move right before the bombs blow so he follows you and gets in the bomb's path. You will have to take some damage from his hammer to pass him.
Collect level 2 to level 8 firepower for your bombs. Plant three to five bombs in the path of the sixth boss. Space them apart at intervals so they will go off one after the other. After five hits, this boss will die.