Saptha Matrikas are supposed to be seven commender in chiefs of Devi's army when Goddess fought Asuras. Each Goddess are known for their paths. While Chamundi fought Munda and chanda , she is known as Chamudi. In Almost all big temples in southern districts , there are images of of Saptha Matrikas in the corridor of Amman sannadhi. I belive in Vidya Upasana , they are known to be important figs. I will throw light more on the subject. i got a picture also i will share with u soon, this is taken in a temple in my native place
Goddess Varahi is one of the Saptamatrukas (Mothers) created from the boar avatara of Lord MahaVishnu. She is classed as the fifth among the seven "mother-like" divinities. Except for Chamundi all the Saptamathrukas represent the female (Shakthi) aspects of the various Gods. Thus, Brahmani represents Brahma, Maheshvari represents Shiva, Kaumari represents Skanda or Muruga, Vaishnavi represents Vishnu, Varahi represents Varaha, the boar incarnation of Vishnu and Indrani that of Indra and Chamundi is the annihilator of Chamunda.
Varahi is the Shakthi energy of the Vishnu Avatar Varaha. She is often associated with Goddess Kamala (one of the Mahavidyas). She is also called the Danda-natha or Lady Commander of the forces of the mother-goddess, symbolizing the might of SriVidya. Varahi is also "Vakdevi" on the snout of Varaha avatara of Lord Vishnu. This Vak (word) is the power of speech of Vishnu in His manifestation as "Yajna Varaha".
Varahi has dominion over the intellect (Bhuddhi) and is worshiped through dhyana yoga. As Varahi she destroys evil forces that obstructs the devotees' progress, paralyses the enemies, and leads the devotees ultimately to Sri-Vidya. With Kurukulla, she is accorded the parental status to Sri-Chakra (Lalita Tripura-Sundari). While Kurukulla represents the full moon, Varahi represents the new- moon. And while Varahi represents the illumination (prakasha) aspects of the mother-goddess, Kurukulla is the "deliberation" (vimarsa) aspect. In another aspect, Varahi is also said to be one of the Yoginis, taking the form of a boar. She is said to lift up the earth with her tusks to confer benefits on all creatures. She is imagined as an eight-armed and three-eyed lady with a face of a hog, seated under a Palmyra tree and functioning as a trusted attendant of the Goddess as her chief counselor. In this form, she is known as Chaitanya-bhairavi (the devotee's association of strength). She is being described as a fierce (Maha-Ghora) and as Commander of the forces, she moves about in a chariot drawn by boars. She is said to reside in the ocean of sugar-cane juice (ikshu), one of the four oceans that surrounds the mother goddess, holding her court in the island of nine-jewels and facing the mother-goddess.