|Location||Plasma Room, Maridia|
|Effect||Greatly increases beam damage and adds piercing effect|
Plasma Beam is the strongest beam upgrade with respect to damage, and causes the beam to pierce vulnerable enemies. Note that it does not allow the beam to penetrate objects and surfaces like Wave Beam does.
Plasma Beam's piercing effect allows the player to be able to "hitbox" enemies. By striking an appropriate enemy with the beam right before Samus would run into them, Samus will instead be able to pass through the enemy unscathed. This is most commonly applied in Lower Norfair rooms containing Kihunters.
From the TASVideos description:
If an enemy is taking damage at the moment its and Samus's hitboxes collide, the hit will not be registered. However, there is little to no chance that Samus will have enough speed to pass the enemy's hitbox by the time it finishes taking damage. By shooting an enemy with a plasma beam, it will become intangible for a number of frames, thus allowing Samus to pass through it easily until that timer runs out and beam finishes colliding with the enemy's hitbox. Note that the enemy that Samus is passing through doesn't need to be actually harmed by the plasma shot to be rendered harmless.
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