Pikachu (SSB)/Back throw
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Pikachu places the opponent on its back, electrocutes them, and knocks them away in the opposite direction it's facing. This throw is very powerful, and is the second most powerful throw in the game, behind Donkey Kong's back throw.
The throw can be used as a part of the Greenhouse combo - after the up tilts, a back throw can be used to launch the opponent up and follow up with a back aerial. However, this is not required to perform the combo.