From the Super Mario Wiki, the Mario encyclopedia
Vegetable is Peach's down special move in the Super Smash Bros. series and Daisy's down special move in Super Smash Bros. Ultimate. Based on the gameplay mechanic from Super Mario Bros. 2, either princess pulls a turnip from the ground, which she can throw at her opponents. When she throws a turnip, it bounces off her opponents, which allows her to grab it again and continue throwing it. The turnips the princess throws do various amounts of damage, depending on its facial expression; the more wrinkled ones do the most damage. Rarely, the princess will pull a Beam Sword (only in Super Smash Bros. Melee and Super Smash Bros. Brawl), Mr. Saturn, or a Bob-omb out of the ground.
In Super Smash Bros. for Nintendo 3DS / Wii U, Vegetable can be customized to one of two variants. The Light Veggie is a slow flying veggie that can be used twice, and when it hits an enemy, it flies back to Peach. The Heavy Veggie takes longer to pull out and has shorter range, but it is stronger. For example, a forward smash-thrown turnip with the wrinkled face can break a full shield in one hit.
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