NARASIMHA AVATAR: This is the lion incarnation where Lord Vishnu adopts a fierce form to protect his ardent devotee, Prahalad. Prahalad was the son of a demon Hiranya-kashipu. Hiranya-kashipu had formerly obtained a boon from Brahma that he would not be killed by a god, man or beast, by any weapon known to man, during the day or night, inside or outside his palace.
Lord Vishnu therefore appeared as a man-beast (half lion and half man); during dusk (which was neither day nor night); on the threshold of his palace (which was neither inside no outside) and destroyed the demon with his claws (which was not a weapon).
This print from the Ravi Varma Press derived from a painting by Raja Ravi Varma depicts Narasimha Avatar as a powerful being of eight arms, six of which are destroying the demon Hiranya-kashipu and two arms carrying the conch (shank) and discus (chakra). He is seen flanked by Prahalad and Lakshmi both in gestures of supplication imploring Narasimha to calm down.