Eggplants

Eggplants are a type of collectible in Super Luigi Country, only being found in Level 14 and the Lost World. They are also a collectible and sort-of the main symbol of the Ice Climber series.

Level 14
In this level, there are 8 Eggplants for you to collect. Three of them are pretty easy to get, One is guarded by Popo, two are guarded by the Polar Bear, and two are guarded by a Nitpicker. Getting all of them will spawn in the Star.

The Lost World
When you enter the Lost World, 7 giant Eggplants are standing there, once you collect them, some purple text will say "you got all the eggplants, look at you".