A Wisdom King is a type of wrathful deity in East Asian Buddhism alsp called Vidyārājas.
Whereas the Sanskrit name is translated literally as "wisdom / knowledge king(s)," the term vidyā in Vajrayana Buddhism is also specifically used to denote mantras; the term may thus also be translated "mantra king(s)."
Vidyā is translated in Chinese with the character 明 (lit. "bright, radiant", figuratively "knowledge(able), wisdom, wise"), leading to a wide array of alternative translations such as .
Heruka, is the name of a category of wrathful deities, enlightened beings in Vajrayana Buddhism that adopt a fierce countenance to benefit sentient beings.
In East Asia, these are called Wisdom Kings.
Herukas represent the embodiment of indivisible bliss and emptiness.
They appear as Iṣṭha-devatā or meditational deities for tantric sādhanā, usually placed in a mandala and often appearing in Yab-Yum.
Heruka represents wrathful imagery with indivisible emptiness (śūnyatā), bliss, peace, wisdom, compassion (bodhicitta), and love. .