Willpower is a light born of The White Light of creation, but in fact is not an emotion, and is represented by the color green. Willpower is in fact a mental ability rather than an emotion, and is defined as "the control of one's impulses and actions". The Emotional Embodiment of this is the Ion Entity. The Guardians of the Universe and later the officers of the Green Lantern Corps wield the Green Light. In order to wield the Green light, one must have enough willpower to overcome great fear.