Guhyagarbha tantra

[1] It is the main Nyingma source for understanding empowerment, samaya, mantras, mandalas and other Vajrayana topics, and has influenced the Dzogchen tradition.

"[1] Morten Ostensen (2019) tenders that the concept of the 'buddha-nature' - specifically as 'sugata-garbha' (Wylie: bde gshegs snying po) - may first have entered the discourse of Tibet and the wider Himalaya through the translation of the Indian Sanskrit manuscript of the Guhyagarbha Tantra in the eighth century - which briefly mentions the sugata-garbha specifically - during the first dissemination or transmission period (Wylie: bstan pa snga dar) of tantra literature into the Himalaya.

The Nyingma school holds that Garab Dorje received the empowerment and transmission of the Mahayoga teachings of the Guhyagarbha from the indian Mahasiddha Kukuraja.

"[1] The Secret Womb texts discuss numerous tantric Buddhist topics, such as the creation of mandalas, the practice of controlling the winds and drops within energy channels, the purification of the five aggregates, and the qualities and activities of the Buddhas.

[1] Nyingma interpreters generally see the Secret Womb Tantra as a guide to the Buddhist practice of Mahayoga, also termed deity yoga, a tantric method of realizing the true nature of reality and attaining Buddhahood.

The peaceful and fierce deities.
Tibetan Thanka depicting peaceful deities, 19th century, Giumet Museum . At the center is primordial Buddha Samantabhadra .
The Wrathful Deities of the Guhyagarbha Tantra . Tibetan thangka from 18th century. Middle figure is Mahottara Heruka, upper left figure is Ratna Heruka, upper right is Padma Heruka, lower center is Buddha Heruka, lower right is Karma Heruka, and lower left is Vajra Heruka. All of them have a consort. Surrounding these figures are the 58 wrathful deities .