I have found both syncretism + paracosm in recent explorations and wish to get your feedback on if / how these processes can help build new myths.
A paracosm is a detailed imaginary world, or fantasy world, involving humans and/or animals, or perhaps even fantasy or alien creations. Often having its own geography, history, and language, it is an experience that is developed during childhood and continues over a long period of time: months or even years.
Syncretism is the combining of different (often contradictory) beliefs, often while melding practices of various schools of thought. Syncretism may involve the merger and analogising of several originally discrete traditions, especially in the theology and mythology of religion, thus asserting an underlying unity and allowing for an inclusive approach to other faiths.