How did shamanic contests between shamans take animal forms?

In the context of shamanism, the combat between two shamans in animal form is considered a defining, albeit rare, trait of the practice, particularly within northern Asian traditions.1

These mystical contests typically involve the shamans assuming the forms of animals, most commonly reindeer or horned cattle. While these battles rarely have a specific, stated purpose, they are viewed as deeds that the shamans are compelled to perform. The outcome of such a struggle is significant for the community: the victory of one shaman is believed to bring well-being, while the defeat of the other results in destruction.1

These transformations are deeply rooted in the shaman's ability to enter a trance state, during which they can communicate directly with the spirit world or allow their soul to leave their body. Such abilities are often supported by guardian spirits that may appear in animal form, and the shaman's performance is frequently accompanied by the use of traditional ceremonial objects, such as drums and specific regalia, to facilitate these supernatural encounters.12