R.O.B. pulls out a Gyro and launches it forward. It's movement varies depending on the stage and gravitational effects. R.O.B. can charge it up to make it launch faster, further and make it spin for longer. this charging technique is similar to Samus's move Charge Shot. To use it once charged, the player must press the Down special attack button when they want to fire it.
Once R.O.B. shoots it, the Gyro can remain on the stage for a while, depending on how long the attack was charged for. R.O.B. or another character can pick it up and throw it again. Until a fired Gyro disappears, the player can't shoot another one. The name comes from the game Gyromite, R.O.B.'s first appearance, and his weapon, the Gyro. [Source: mariowiki]
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