Siddhayoga
The Tirtha lineage of Siddhayoga is a mystical sect of Shaivite Hinduism. It believes in direct encounters with life-force or kundalini shakti, and understanding of the Shastras. It places importance on the guru-disciple bond, as, according to this tradition, the guru transfers shakti, the divine energy, to the disciple through a transformative process known as Shaktipat. Shakti is said to be automatically infused into a disciple by a guru in a process called Shaktipat.
Within the realm of Siddhayoga, numerous lineages exist, while there are also various groups that, despite not using the specific name, discuss the infusion of kundalini shakti. Some lineages share a common origin, while others have no connection whatsoever. Siddhayoga also has similarities to sahajayoga, mahayoga or siddhamahayoga. Similar teachings may be traced back at least to the Tantric masters such as the scholar Abhinavagupta. Shakti is held to be the energy of a universal soul, of which direct experience is believed to be available regardless of religion; thus siddhayoga is sometimes considered a universal, rather than a strictly Hindu, practice.