Vajrasattva purification

“Vajrasattva purification” is the visualization of the Buddha Adamantine Hero (Rdo rje sems dpa’ [Dorjé Sempa]; Skt., Vajrasattva) above the crown of one’s head, while reciting his hundred-syllable mantra revolving around his heart. The practitioner confesses downfalls, and visualizes that luminous ambrosia flows from Vajrasattva’s heart to transform the practitioner’s negativity into sustenance for suffering beings.

In the context of this being part of the “extraordinary preliminary practices” (sngon ‘gro) one is required to do before engaging in advanced tantric contemplation, one is expected to do this 100,000 times.