(“aggressive”) Durga and Kali are two ferocious and strong deities who are given this epithet.
Chandika is a variant form of Chandi, and it is under this name that Chandi is recognized as one of the Navadurgas, the "nine [forms of the goddess] Durga" adored during the Navaratri festival's nine nights.
Chandika is the most powerful of these heavenly forms, since she is adored during the festival's ninth and last night.
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