The Screwattack is a very powerful weapon which basically consists of it's user spinjumping while unleashing a spinning vortex of energy that damages most enemies or breakable objects.
It appears in most Metroid games and all 2D games.
This marks the Screw attacks first appearance in the Metroid series.
The screw attack is located in Norfair and functions the same way as mentioned earlier although it cannot be stacked with Space jump as it doesn't exist in this game.
 Metroid 2
The screw attack makes it second appearance in The second game of the franchise and functions the same way as mentioned earlier.
It is one of the final items picked up in the game and is picked up in the 4th Chozo City.
It can be used to hurt\kill enemies and destroy breakable blocks but it cannot harm Metroids.
 Super Metroid
The screw attack reappears in its first 16bit debut in Super Metroid.
You obtain the Screw Attack in Lower Norfair after defeating the final Torizo, the powerful Gold variant.
Behavious more or less the same way as it did in the previous games however it can be stacked to the Space Jump which doesn't appear in the Original two games.
Samus can preform a mini Screw Attack without having the actual power up using the Charge Beam
It's far less powerful that the Screw Attack but can be quite helpful early on particularly with avoiding enemy projectiles.
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