Siddhidatri  –  The siddhidatri devi is the one goddess out of the nine goddess.In this form siddhidatri Durga devi is seated on a lotus and has four armed. She holds a lotus, mace, discus and book. There are eight Siddhis , they are- Anima, Mahima, Garima, Laghima, Prapti, Prakamya, Iishitva & Vashitva. Maha Shakti gives all these Siddhies to us. In this form Durga removes ignorance and she provides the knowledge . The Goddess rides on the Lion. This form of Durga is worshipped by all Gods, Rishis-Munis, Siddhas, Yogis, Sadhakas and devotees for attaining the best religious asset and siddhies.Siddhidatri form of Durga is worshipped on the ninth day of Navaratri or Navdurga puja i.e. ashwini shukla navami.
Mantra of Maa Siddhidatri devi  :

Siddh Gandharv Yagyadyair Surair Marairapi !
Sevyamana Sada Bhooyaat Siddhida Siddhi Dayanee  !!