The Seven Godesses in Devi-Mahatmyam

In the 3rd episode of Devi-Mahatmya, the demons Sumbha and Nisumbha, having asurped the Gods from their positions, confronted the Devi in the battle field. As the Demon Armies approach the Devi, the male Gods created their Sakthis as female counter parts to help in the battlefield. Thus seven such Sakthies were created resembling closely the male Gods from whom they are said to have arisen. Basically all the Seven were Fierce Godesses and invariably associated with Para-Devata in her battle against Demons or Asuras.

Thus,
Brahmi was created from the God Brahma with Akshamala and Kamandalu riding a Swan. Maaheswari created from Shiva adorned with a Crescent Moon wore Serpent Ornaments in her limbs, held a Trident and rode a Bull. Kaumari created from Karthikeya rode a Peacock and held the Spear. Vaishnavi created from Vishnu rode a Garuda holding a Coch, Discus, Mace, Bow and sword. Vaarahi created from Varahamurthy was in the form of a Boar like Varaha Avatar of Vishnu. Narasimhi created from Narasimha Avatar of Vishnu had the form of She-Lion. Aindri created from Indra held the Thunderbolt in her hand and rode an Elephant.

Collectively called as Sapta-Matrukas, they brought havoc to the Demon Armies. In this Slaughter they were also assisted by Kali ( Also called as Chamunda ) and Sivadhuti ( Created from Devi herself ). In their Victory over the Demons they danced after the battle having been drunk with the blood of their victims. Subsequently after Nisumbha was killed, Sumbha challenged the Devi for a Single “One-on-one” Combat. In acceptance Devi absorbed all the Sapta-Matrukas within herself referring them as different manifestation of herself.

In the tenth Chapter called "The Slaying of Sumbha" of Devi Mahatmya in Markandeya purana, their conversation is quoted as follows :-
(1-3) The Rishi said :
Seeing his brother Nisumbha slain, who was dear to him as his life, and his army being slaughtered, Sumbha angrily said ,"O Durga who are puffed up with the pride of strength, don't show your pride ( here). Though you are exceedingly haughty, you, resorting to the strength of others, fight"
(4-5) The Devi said :
I am all alone in the world here. Who else is there besides me ? See, O vile one, these
Goddesses, who are but my own powers, entering into my own self !
(6) Then all those, Brahmani and the rest, were absorbed in the body of Devi. Ambika alone then remained.
(7-8) The Devi said :
The numerous forms which I projected by my power here - those have been withdrawn by me (now) I stand alone. Be Steadfast in combat.

Extract from the English Translation by Swami Jagadiswarananda of Sri Ramakrishna Math of Devi Mahatmyam ( Glory Of The Divine Mother ), Mantras of the Sri Durga :-

From The eight Chapter called "The slaying of Raktabija" of Devi-Mahatmya in Markandeya Purana.

12-13. "At this moment, O King, in order to annihilate the enemies of devas and for the well-being of the supreme devas, there issued forth, endowed with exceeding vigour and strength, Saktis from the bodies of Brahma, Siva, Guha, Visnu and Indra, and with the form of those devas went to Candika…

14. Whatever was the form of each deva, and whatever his ornaments and vehicle, in that very form his saktis advanced to fight with the asuras.

15. In the heavenly chariot drawn by swans advanced Brahma's Sakti carrying a rosary and a Kamandaly. She is called : Brahmani.

16. Mahesvari arrived, seated on a bull, holding a fine trident, wearing bracelets of great snakes and adorned with a digit of the moon.

17. Ambika Kaumari , in the form of Guha holding a spear in hand riding on a fine peacock, advanced to attack the asuras.

18. Likewise, the Saktis of Visnu came, seated upon Garuda, holding conch, club, bow and sword in hand.

19. The Saktis of Hari, who assumed the incomparable form of a sacrificial boar, she also advanced there in a boar-like form.

20. Narasimhi arrived there, assuming a body like that of a Narasimha, bringing down the constellations by the toss of her mane.

21. Likewise the thousand-eyed Aindri, holding a thunderbolt in hand and riding on the Lord of elephants arrived just like Sakra ( Indra )

22. Then Siva, surrounded by those saktis of the devas, said to Candika, 'Let the asuras be killed forthworth by you for my gratification."

23. Thereupon from the body of Devi Issued forth the Sakti of Candika, most terrific, exceedingly fierce and yelling like a hundred jackals.

24. And that invincible ( Sakti ) told Siva, of dark coloured matted locks, "Go my lord, as ambassador to the presence of Sumbha and Nisumbha"

25. "Tell the two haughty asuras, Sumbha and Nisumbha, and the other asuras assembled there for battle.

26. "Let Indra obtain the three worlds and let the devas enjoy the sacrificial oblations. You go to the nether world, if you wish to live.

27. But if through pride of strength you are anxious for battle, come on then. Let my jackals be satiated with your flesh."

28. Because that Devi appointed Siva himself as ambassador thenceforth she became renowned in this world as Siva-duti.

32. Then, in front of him ( Sumbha ), stalked Kali, piercing the enemies to pieces with her spear and crushing them with her skull-topped staff.

33. And Brahmani, wherever she moved, made the enemies bereft of valour and prowess by sprinkling on them the water from her Kamandalu.

34. The very wrathful Mahesvari slew the daityas with her trident, and Vaisnavi, with her discuss, and Kaumari with her Javelin.

35. Torn to pieces by the thunderbolt which come down upon them, hurled by Aindri, daityas and danavas fell on the earth in hundreds, streams of blood flowing out of them.

36. Shattered by the boar-formed goddess Varahi with blows of her snout, wounded in their cheats by the point of her tusk and town by her disucss, the asuras fell down.

37. Narasimhi, filling all the quarters and the sky with her roars, roamed about in the battle, devouring other great asuras torn by her claws.

38. Demoralised by the violent laughter of Sivaduti, the asuras fell down on the earth; She then devoured them who had fallen down.

39. Seeing the enraged band of Matrukas, crushing the great asuras thus by various means, the troops of the enemies of devas took their heels.

40. Seeing the asuras harassed by the band of Matrukas and fleeing, the great asuras Raktabija stroded forward to fight in wrath.

41. Whenever from his body there fell to the ground a drop of blood, at that moment rose up from the earth asuras of his stature.

42. The great asuras fought with Indra's Sakti with club in his hand; then Aindri also struck Raktabija with her thunderbolt.

43. Blood flowed quickly and profusely from him, who was wounded by the thunderbolt. From the blood rose up
( fresh ) combatants of his form and valour.

44. As many drops of blood fell from his body. So many persons came into being, with his courage, strength and valour.

45. And those persons also sprung up from his blood fought there with the Matrukas in a more dreadful manner hurling the very formidable weapons.

46. And again when his head was wounded by the fall of her thunderbolt, his blood flowed and there from were born persons in thousands.

47. Vaisnavi struck him with her discuss in the battle, Aindri beat that Lord of Asuras with her club.

48. The World was pervaded by thousands of great asuras who were of his stature and who rose up from the blood that flowed from him when cloven by the discuss of Vaisnavi.

49. Kaumari struck the great asuras Raktabija with her spear, Varahi with her sword, and Mahesvari with her Trident.

50. And Raktabija, that great asuras also, filled with wrath, struck everyone of the Matrukas severally with his club.

51. From the stream of blood which fell on the earth from him when he received multiple wounds by the spears, darts and other weapons, hundreds of asuras came into being.

52. And those asuras that were born from the blood of Raktabija, pervaded the whole world; the devas got intensely alarmed at this.

53. Seeing the devas dejected, Candika laughed and said to Kali ."O Chamunda, open out your mouth wide, with this mouth quickly take in the drops of blood generated by the blow of my weapon and (also) the great asuras born of the drops of blood of Raktabija.