Three-ball blast

The three-ball blast is an attack used by the Queen Metroid in Metroid II: Return of Samus.

Description
In Return of Samus, the Queen Metroid has a simple attack pattern: after performing two long-necked attacks, she retreats into her den and performs the three-ball blast. These fireballs are projectiles that the Queen Metroid spits from her mouth, always three at a time. Once expelled, the fireballs home in on Samus Aran and deal damage. The most effective means of dealing with the three-ball blast is by using the Screw Attack, which instantly dispels each fireball on contact without taking any damage.

The Queen Metroid no longer spits individual fireballs in Metroid: Other M or Metroid: Samus Returns; instead, she breathes a steady stream of fire. However, the Queen Metroid has a very similar attack in Samus Returns, starting in the second phase of the battle. When her eyes and throat glow green, she spits out a large number of green projectiles that slowly float around the chamber, severely limiting Samus's ability to move without taking damage. Unlike Return of Samus, the Screw Attack has no effect on these projectiles, and she will take damage unless the Lightning Armor is active. The Queen Metroid always pairs this attack with at least one other attack (the fire breath and/or wind gust); however, these projectiles will instantly be dispelled if Samus interrupts the Queen Metroid's fire breath with a Spider Boost. It is unclear if these projectiles are meant to be acid, plasma, or some other substance.

Nintendo Power Volume 37

 * PHASE 9 : THE FINAL BATTLE
 * "Avoid the Fireballs or tear them up with the Screw Attack."