Since time immemorial, animal skin is the traditional garment worn by the dukun (shaman), bomoh (sorcerer), pawang (magician), and rêsi (seer). In the old days, mystics and ascetics used to wear traditional clothing made from tiger skin, like in Sumatra, for example. In more recent times, however, the Sumatran tiger had become a critically endangered animal, and thus many Indonesian dukuns soon resorted to deer skin, an ancient garment still worn by traditional mystics in Java today.
Wearing deer skin as garment mainly serves a practical purpose, because it helps to keep bugs and insects away when the mystic is wandering through the forest. Javanese dukuns generally find it very important to have their traditional garment made from genuine deer skin, for it allows them to perform their spiritual practice in seclusion, i.e. to perform the practice of meditation whilst they reside in the forest, far away from society. In fact, the use of animal skin for traditional garment originates from ancient India, where the Brahman rishis (Sanskrit: ṛṣi; Javanese: rêsi) and other renunciants would cover their private parts with a piece of tiger, leopard, panther, or deer skin, as they dwelt in remote areas to perform austerities.
The forest is commonly known as a place full of dangers. If one wants to survive in the jungle, then it is absolutely crucial to have some form of protection against the danger of wild animals and deadly insects living in this rough terrain. Though wearing the skin of a dead animal naturally instills fear among forest creatures, yet this is not enough to keep other forms of danger away as well. Indeed, there are various kinds of nature spirits and ghosts who can do a person serious harm if s/he fails to pay proper respect towards the spirit beings that reside in the area.
For this reason, then, Mbah Joyo – a traditional Javanese dukun renown for his extraordinary mystical abilities – performed handwritten spell inscriptions and sacred geometric symbols on the deer skin. Hence, the Javanese deer skin is richly endowed with powerful mystical properties to ward off all evil. With this whole deer skin in one's possession, one need not worry about potential threats of danger, for indeed, no sentient being (including black magicians and the evil jinn they summon) can come anywhere near you because of the magical power of the spells and incantations by which the deer skin was consecrated. This is, therefore, an incredibly rare opportunity to obtain a true mystical object of tremendously sacred value.