Dharma Protector (Skt: dharmapala) is a wrathful deity, pledged to defend the Dharma, its practitioners, their practice, progress etc. Dharmapalas often have blue, black or red skin, and a fierce expression with protruding fangs.
Though dharmapalas have a terrifying appearance and countenance, they are all bodhisattvas or buddhas, meaning that they are the embodiment of compassion that acts in a wrathful way for the benefit of sentient beings.
Whether one stays in a monastery or continues to live in daily life while practicing the higher Tantras, one really needs all protection one can get. And Dharma Protectors are most needed.
In the Vajrayana practice, we rely on various dharmapalas: Mahakala, Palden Lhamo, Vaishravana, Yamantaka etc…
The wrathful deity Palden Lhamo ( Skt: Shri Devi or Remati) is one of the main Dharma protectors in the Gelug school of Tibetan Buddhism and considered to be the tutelary deity of Tibet and its government”, and as “celebrated all over Tibet and Mongolia, and the potent protector of the Dalai and Panchen Lamas and Lhasa.”
The detailed iconography of Palden Lhamo is complicated, and this is not the place to discuss it. Jeff Watt wrote an excellent article on the Himalayan Art site about it. In the context of the Gelugpa school of Tibtean Buddhism we deal specifically with the form of Magzor Gyalmo meaning “Glorious Goddess, the Queen who Repels Armies”, or “the Queen who has the power to turn back armies”. She has a blue-black body and and a fiercly wrathful expression, has one face and two hands, holding aloft with the right hand a vajra-tipped staff and in the left a skullcup held to her heart. She rides on a side-saddle atop a mule. Above her head is a large peacock feather parasol.
This dark-blue/black form of the six-armed (Skt: Shadbuja) Mahakala (also called “Nagpo Chenpo”, Tib: gnag po chen po; or by the Tibetans just “lord”, Tib: mGon po) was originally brought to Tibet by Khyungpo Naljor, the founder of the Shangpa Kagyu School. It became popular in the Sakya and Kagyu traditions and was later adopted into the Gelugpa School, becoming the principal protector. There is also a White Six-Armed Mahakala (Skt: Shad-bhuja Sita Mahakala; Tib: mGon po yid bzhin nor bu) popular among Mongolian Gelugpas and the Shangpa Kagyu School.
“The Lord of Pristine Awareness has six hands and a body dark blue in colour. The first two hold a curved knife and skullcup, the middle two a human skull mala and trident, the lowest two a damaru drum and lasso. Adorned with a tiger skin, garland of heads, bones and snakes, and small bells on the hands and feet. Standing in a manner with the two legs together pressing down on Ganapati. With three eyes, bared fangs, eyebrows, beard and hair flowing upward with Akshobhya as a crown. Anointed with a sindhura drop on the forehead. Supported behind by a sandalwood tree, dwelling in the middle of a blazing mass of fire.” (Jonang Taranatha, 1575-1634).
Vaishravana is usually portrayed with a stern look and two large staring eyes, one face and two hands. In his right hand he holds a victory banner of variously colored fluttering silks – a gift of the gods, and with his left he holds a black mongoose spitting a flood of colored jewels collecting on the moon disc below. Adorned with a gold and jewel crown, earrings, body armor of gold, garments of various colours, pants and boots, he sits in a relaxed posture with the right leg extended atop a snow lion.