A set of preparatory practices undertaken by adherents of Tibetan Buddhism to accumulate sufficient merit (puṇya) to enable the practitioner to engage subsequently in tantric practices. Though the set of practices is overall identical, each school of Buddhism in Tibet follows its own specific tradition due to devotional and doctrinal differences. Typically, the preliminary practices comprise two parts, the ordinary and the extraordinary practices. The former includes meditations on the precious human existence, impermanence (anitya), the defects of saṃsāra.the workings of karma and the need for a spiritual guide or guru. The extraordinary practices are suffused with a tantric approach and include the taking of refuge (see triśaraṇa), generation of the aspiration to enlightenment (bodhi), recitation of the Vajrasattva mantra.the offering of maṇḍalas.and guru yoga. The extraordinary practices are done, usually in sequence, for a minimum of 100,000 times each.