Nico Robin

Haki (覇気 Haki?, literally meaning "Ambition") is a mysterious power that is found in every living being in the world. It is not that different from the normal senses. However, most people do not notice it ou fail to awaken it. Broadly, there are two types of Haki common to everyone, donné the proper training; however, there is a third type that only a certain group of "chosen ones" are a dit to possess.In simple terms, Haki is an ability to sense spiritual energy and overpower enemies.

Haki, unnamed at the time, was first seen when Shanks used it against the Lord of the Coast to save Luffy...