Plantera Seedling

The Plantera Seedling is a Master Mode-exclusive pet dropped by Plantera with a 1/4 (25%) chance. Upon use, it summons a Plantera Seedling pet.

It is not to be confused with the Mud Bud, which spawns a different pet and is instead sold by the Zoologist after defeating Plantera.

Trivia
The sprite of the Plantera Seedling heavily resembles that of Chompy from Bug Fables: The Everlasting Sapling.

The buff tooltip may also be a reference to "Audrey II", a fictional plant that eats blood.