The Jaganmangala Kavacham — also called the Shyama Kavacham — is a tantric armour of Kali preserved in the Bhairava Tantra (and in the Shakta Pramoda compilation). Bhairavi, the Goddess, asks her consort Bhairava for the armour he had promised, and he reveals it as “the body of the mantras”: whoever reads or wears it can enchant the three worlds.
Bhairava gives its power through stories: wearing it, Narayana took the form of the enchantress Mohini; wearing it, Rama killed Ravana; by its grace Bhairava himself conquered the three worlds, Kubera became lord of wealth and Indra king of the gods.
The armour itself is built from mantra. Kali’s seed syllables — Krim, Hum, Hrim, Aim — and her famous mantras of one, three, six, seven, eight, ten, fourteen and twenty-two syllables are placed on the head, forehead, eyes, ears, nose, tongue, face, shoulders, heart, arms, navel, back and legs. Then her forms — Kapalini, Kulla, Kurukulla, Viprachitta, Ugra and the rest — and the eight Matrikas (Brahmi, Narayani, Maheshvari, Chamunda, Kaumari, Aparajita, Varahi and Narasimhi) guard every direction with their weapons.