Simhamukha is a generic term applying to various lion-headed deities, usually female. Simhamukha may be a buddha emanation and tantric deity, a wisdom dakini, a Bardo deity. For more information see the Himalayan Art Resources website and http://vajranatha.com/teaching/Simhamukha.htm
This is a rare form of a lion-headed deity seated on Ganapati, wearing a garland of severed heads, a five-skull crown, some jewellery, and holding a long-life vase in both hands. Christie’s tell us that there is an elephant hide on her back.
This Simhamukha has cold gold and pigments on her face to highlight her three eyes, furling tongue and bared fangs; her flaming hair is dyed orange. She wears a garland of large human heads around her neck, a bone cross-belt across her chest, and holds a flaying knife in her right hand at head level, and skull cup filled with blood against her heart.
The above holds both her flaying knife and skull cup at heart level and has a ritual staff tucked against her left arm. She has human ears and wears a garland of 50 skulls, a festooned and foliate five-skull crown, bone jewellery, a bone apron and a celestial scarf with serpentine ends. Both feet trample on Ganapati. There is no flaming hair visible but a flaming arch around her.
This simhamukha also stands on both feet over a (very flattened) victim. She sports large curls of flaming hair.
Simhavaktra is an attendant to Palden Lhamo. As such, she is part of a set including the latter and always smaller than her. She has a dakini appearance, standing in a dancing posture, her left foot trampling a victim (missing here), her flaming hair erect, wearing a garland of freshly severed heads and a tiger skin loincloth, wielding a flaying knife and holding a skull cup filled with blood at heart level. The artist has given her large lion ears and abundant lion hair over the forehead. The iconography is identical to that of Simhamukha the wisdom dakini.
A particularly fierce example, standing on a victim within a triangle over a lotus base with a single row of petals going downwards.
A variant with both feet on the (missing) base and a human hide across her back, no garland of severed heads or skull crown.