Eggplant was or is a planned unit in Plants vs. Zombies: All Stars that is not available in the game (yet?), but we can find it in the game files.
In Chinese version of Plants vs. Zombies 2 there is an Eggplant Ninja unit. It attacks by throwing shurikens at zombies which will damage it until it dies. In addition, every fifth Eggplant Ninja to be planted will release a tornado shuriken which will send the targeted zombies off-screen. It has “Legendary” rarity and is unlocked by collecting 10 Eggplant Ninja puzzle pieces.