Rigdzin Düpa Puja (Guru Rinpoche Day)

Rigdzin Düpa, ‘The Gathering of Vidyadharas,’ is the inner lama practice from the Longchen Nyingtik, the terma revelation of Jikmé Lingpa.
Thank you to DharmaSubhashita for this description:
Rigdzin Düpa (The Gathering of Awareness Holders -vidyadhara) is the inner (amongst outer, inner, secret and innermost secret) level of Guru-Yoga from Longchen Nyingtik. In this practice Guru Rinpoche (Padmasambhava) appears along with Mandarava and the eight great vidyadharas. The elaborate Tsok performed at most Nyingma monasteries is based on the Rigdzin Dupa sadhana.
Longchen Nyingtik (The heart essence of the great expanse) is one of the most widespread cycles of treasure teachings (terma) in Nyingma tradition. It was revealed by the great scholar and yogi, Vidyadhara Jigme Lingpa as a mind treasure – from the enlightened nature of mind. This cycle of teachings originated from the primordial Buddha Samantabhadra, and came down through an unbroken lineage involving Vajrasattva, Prahevajra, Vimalamitra, Padmasambhava, Longchenpa, Jigme Lingpa, etc. Rigdzin düpa is the inner Guru practice from this treasure cycle.