Mother Brain part 2 beaten using the Murder Beam. Played in real time on Snes9x v1.43 rerecording.
To use the Murder Beam, charge up your beam and then pause the game. Go to the inventory screen, equip all beams but the Plasma Beam, then move the cursor onto the Speed Booster. Now push left on the control cross and the A button at exactly the same time to equip both the Spazer and Plasma beams. Unpause the game, fire the charged shot into Mother Brain's head while it's still sitting on the floor, then disequip the Spazer Beam again.
Be careful when using the Murder Beam. If you fire it in any direction other than straight left, or if you fire an uncharged shot at all, the game will freeze. This is because there's no sprite in the game to display both the Spazer and Plasma Beams being fired together, and the game just doesn't know what to make of it.
The actual effect that the Murder Beam has is creating an invisible wall of damage. Anything to the left of where the Murder Beam shot impacts (in this case, where Mother Brain's head was on the floor) will take constant damage. This is only practical against Mother Brain, however, since she's the only boss that will consistently stay to the left of where the shot can impact.
![](https://i.ytimg.com/vi/YqIManl66uQ/mqdefault.jpg)