The Yantra is said to enhance the chances of the Sadhaka in invoking Bhairava, if it is prepared for 15 days in a row at night in a Smashan Bhoomi [Hindu Crematorium].However, the exact specifications for the making of the Yantra [the ink, pen and material] is best left to the Sadhaka as it largely depends upon the kind of invocation Mantra-Tantra experiment he is engaged in for invoking Bhairava.
As pointed out above and also in many earlier posts, such Tantric experiments for invoking and having vision or Darshan of the most powerful Hindu deities like Hanuman, Kali Mata and Bhairava are extremely difficult Sadhanas and best left to those Tantric practitioner in the most advanced stages of Hindu occult practices.
|Bhairav Siddhi Yantra|
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Smashan Kali Vashikaran Mantra (prophet666.com)
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Mantra to call Soul of the Dead (prophet666.com)
Sankat Mochan Hanuman Yantra (prophet666.com)
Kalika Siddhi Mantra (prophet666.com)
Disha Bandhan Mantra Sadhana in Shivalaya (prophet666.com)
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Hatha Jodi Mantra for Money (prophet666.com)
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