Asatru (Norse Heathenism): 

Asatruar may utilize improv in blóts and symbels, adapting offerings, invocations, and toasts based on the immediate interaction with the gods and ancestors.

Buddhism:

   - In certain Buddhist meditation practices, practitioners might be encouraged to embrace the present moment and improvise their meditation techniques based on their current state of mind and emotions.

Christianity (Oceania):

    - In Pacific Islander Christian communities, during religious ceremonies and gatherings, individuals might share spontaneous testimonies and personal stories of faith and conversion.

Christianity (South America):

   - During Christian processions or festivals in South America, participants might improvise songs, chants, or prayers to celebrate religious events and express their devotion.

Christianity (USA):

   - During worship services, individuals may spontaneously call out, perhaps for healing or guidance. Some Christians believe that a "Holy Ghost" inspires and guides these prayers.

Eclectic Paganism: 

In eclectic pagan practices, improv can be integrated into rituals to draw from multiple traditions and deities, facilitating personal spiritual connections and individualized ceremonies.

Hellenism: 

Hellenists might use improv during devotional ceremonies and libations, spontaneously expressing gratitude and seeking guidance from the ancient Greek deities.

Hinduism:

   - In Hindu temple rituals, priests may improvise or adapt prayers and hymns to accommodate specific occasions or worshipers' needs, making the ceremonies more relevant and personal.

Hermetic Order of the Golden Dawn:

 Occultists in the Golden Dawn may use improv in their ceremonial magic to spontaneously respond to astral influences and adapt rituals based on individual initiates' progress.

Indigenous African Religions

   - In some African traditional rituals, dance performances might include improvised movements and gestures, expressing the spiritual connection between participants and the spirits or deities.

Islam:

   - During Islamic gatherings or Sufi sessions, participants might engage in improvised spiritual songs and dances, expressing their devotion and spiritual experiences spontaneously.

Islam (North America):

   - In American Muslim communities, participants in Islamic study groups might engage in improvised discussions and debates, exploring various interpretations of religious texts and teachings.

Judaism:

   - In Jewish mystical practices, adherents might engage in spontaneous meditation and contemplation, allowing insights and spiritual experiences to arise naturally.

Kemeticism: 

Kemetic practitioners may use improv in offerings and prayers, adapting their rituals based on the immediate interaction and guidance from the Egyptian deities.

Magick: 

Magicians embrace improv as a central tenet, using belief shifting and adaptable rituals to access the desired states of consciousness and manifest their intentions effectively.

New Age Spirituality: 

In New Age practices, improv is employed to explore diverse spiritual techniques, allowing practitioners to find what resonates best for their personal growth and self-discovery.

Shamanism: 

Shamans employ improv during healing ceremonies and spirit journeys to adapt their actions and guidance based on the interactions with spirits and the specific needs of the individuals seeking healing.

Sikhism:

   - Sikh kirtans (devotional singing) may involve improvising melodies and lyrics, allowing musicians and devotees to connect more deeply with the divine and express their feelings authentically.

Theosophical Society: Theosophists might engage in improv to explore higher consciousness and connect with spiritual beings, allowing for spontaneous insights during their study and meditation sessions.

Traditional Witchcraft: 

Traditional witches may use improv in folk magic spells and rituals, creatively adapting chants, gestures, and ingredients to suit the immediate circumstances and the spirits involved.

Vodou (Voodoo): 

In Vodou ceremonies, improv can be employed to embody the loa (spirits) and allow them to spontaneously communicate and offer guidance to the community through the possessed practitioners.

Wicca: 

Wiccans may use improv during rituals to channel spontaneous energy and creatively adapt their ceremonies based on the flow of the group's energy.