Mastering

Mastering is a giant mutant poring that always carries normal Porings with it. A giant Poring rarely seen in the Sograt Desert, Mt. Mjolnir, or the Prontera Maze. It may be the master of Porings, but... it's still a Poring.

Ragnarok Online II
In RO2, Mastering is simply a Poring that is slightly bigger than regular ones with a crown and sunglasses. It has the ability to corrupt Porings into Poor Porings.