In the succession of religions, there are only so many ways the old gods can end up. They can fade away, in which case they are lost to us for good; they can be held up to scorn as pagan demons who persisted in their old, evil ways; or they can be recruited into the new faith as its servants and defenders.
[…] This pattern of subjugation and conversion had already occurred during the rise of Buddhism in India with the Vedic gods and demons (the deva and the asura). Indra, the storm god of the warriors, became Sakra, who piously requested teachings from the Buddha. Brahman, the creator god, turned into a defender of the Law. Lesser deities too resurfaced in new roles. The nymph-like yaksi came to decorate the gates of the stupas at Sanchi, and heavenly nymphs became angelic musicians, scattering flowers in the air (they remained scantily dressed, as fertility deities should). Satyr-like yaksas ran errands for Yama, the old moon god who now supervised the Buddhist hells, and so on. Their fate is not unlike that of the gods of Old Europe. Those who did not fade away ended up either as denizens of hell or as saints in the Christian calendar.
[…] This is not an uncommon fate for the old chthonic gods. In India an equally insatiable “Face of Glory” is stationed outside temples, supposedly to scare away the evil spirits. In Rome, the griffin was the guardian of the sarcophagus (which means “meat-eater”). In medieval Europe, gargoyles likewise crouched watchful on eaves. In Egypt, Anubis the Jackal – Dog-Man by another name – witnessed the weighing of souls. In Buddhism, Mara the Devil holds samsara in his jaws. In Tang China, a pair of life-size hounds with human heads (and sometimes single horns) stood guard near the dead.