Vajrapani Iconography Page
There are several famous traditions of the Nilambara Vajrapani such as the Drozang and Sakya lineages. The most famous tradition to promote and practice the Nilambara is the Shalu monastery. In the Sakya tradition the Bhutadamara and the Nilambara are the two most important forms of Vajrapani.
Jeff Watt 4-2020
84000: Translating the Words of the Buddha: Nilambara Vajrapani (Bhagavannīlāmbaradharavajrapāṇitantra, bcom ldan ’das phyag na rdo rje gos sngon po can gyi rgyud ces bya ba)