Khenpo Namdrol presents a lucid and detailed explanation of the history and practice of Vajrakilaya.
"The practice of Vajrakilaya blazes at the heart of the ancient Vajrayana traditions of Tibet. The wrathful heruka Vajrakilaya is the yidam deity who embodies the enlightened activity of all the buddhas manifesting in an intensely wrathful yet compassionate form in order to subjugate the delusion and negativity that can arise as obstacles to the practice of Dharma. In fact, the practice of Vajrakilaya is famous in the Tibetan Buddhist world as the most powerful for removing obstacles destroying the forces hostile to compassion and purifying the spiritual pollution so prevalent in this age."—Sogyal Rinpoche