Tantra
https://en.wikipedia.org/wiki/Kali
Kali Yantra
Goddesses play an important role in the study and practice of Tantra Yoga, and are affirmed to be as central to discerning the nature of reality as are the male deities. Although Parvati is often said to be the recipient and student of Shiva's wisdom in the form of Tantras, it is Kāli who seems to dominate much of the Tantric iconography, texts, and rituals.[7] In many sources Kāli is praised as the highest reality or greatest of all deities. The Nirvana-tantra says the gods Brahma, Vishnu, and Shiva all arise from her like bubbles in the sea, ceaselessly arising and passing away, leaving their original source unchanged. The Niruttara-tantra and the Picchila-tantra declare all of Kāli's mantras to be the greatest and the Yogini-tantra, Kamakhya-tantra and the Niruttara-tantra all proclaim Kāli vidyas (manifestations of Mahadevi, or "divinity itself"). They declare her to be an essence of her own form (svarupa) of the Mahadevi.[8]
In the Mahanirvana-tantra, Kāli is one of the epithets for the primordial sakti, and in one passage Shiva praises her:
At the dissolution of things, it is Kāla [Time] Who will devour all, and by reason of this He is called Mahākāla [an epithet of Lord Shiva], and since Thou devourest Mahākāla Himself, it is Thou who art the Supreme Primordial Kālika. Because Thou devourest Kāla, Thou art Kāli, the original form of all things, and because Thou art the Origin of and devourest all things Thou art called the Adya [the Primordial One]. Re-assuming after Dissolution Thine own form, dark and formless, Thou alone remainest as One ineffable and inconceivable. Though having a form, yet art Thou formless; though Thyself without beginning, multiform by the power of Maya, Thou art the Beginning of all, Creatrix, Protectress, and Destructress that Thou art.[7]
The figure of Kāli conveys death, destruction, and the consuming aspects of reality. As such, she is also a "forbidden thing", or even death itself. In the Pancatattva ritual, the sadhaka boldly seeks to confront Kali, and thereby assimilates and transforms her into a vehicle of salvation.[9] This is clear in the work of the Karpuradi-stotra,[10] a short praise Kāli describing the Pancatattva ritual unto her, performed on cremation grounds. (Samahana-sadhana)
He, O Mahākāli who in the cremation-ground, naked, and with dishevelled hair, intently meditates upon Thee and recites Thy mantra, and with each recitation makes offering to Thee of a thousand Akanda flowers with seed, becomes without any effort a Lord of the earth. 0h Kāli, whoever on Tuesday at midnight, having uttered Thy mantra, makes offering even but once with devotion to Thee of a hair of his Shakti [his energy/female companion] in the cremation-ground, becomes a great poet, a Lord of the earth, and ever goes mounted upon an elephant.[9]
The Karpuradi-stotra clearly indicates that Kāli is more than a terrible, vicious, slayer of demons who serves Durga or Shiva. Here, she is identified as the supreme mistress of the universe, associated with the five elements. In union with Lord Shiva, who is said to be her spouse, she creates and destroys worlds. Her appearance also takes a different turn, befitting her role as ruler of the world and object of meditation.[11] In contrast to her terrible aspects, she takes on hints of a more benign dimension. She is described as young and beautiful, has a gentle smile, and makes gestures with her two right hands to dispel any fear and offer boons. The more positive features exposed offer the distillation of divine wrath into a goddess of salvation, who rids the sadhaka of fear. Here, Kali appears as a symbol of triumph over death.[12]