Following is the most simple one letter Mantra for gaining the great paranormal powers of Asht Siddhi and Khechari Siddhi.

One must keep a Shri Yantra in front of him while chanting the Mantra given below and should use a Manas Siddhi rosary or Karya Siddhi Rudraksh Mala for success. The Mantra should be chanted 3 lac times for getting the desired success in mastering and each of the two Siddhis.  - Ashok Mehta
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