The Mist Possessed originated when construction upstream disturbed ancient spawning grounds, releasing aquatic spirits that merged with the morning fog. These spirits now seek hosts among wildlife and players, creating possessed forms that defend the creek's territory. The transformation escalates with each fog event, turning victims into relentless enforcers of the aquatic horror.

The Mist Possessed shifts between semi-corporeal and ethereal states, gaining solidity in dense fog while moving silently without disturbing water. It possesses enhanced strength and agility, causes localized temperature drops, and amplifies fog density to reduce visibility. Vulnerable to sunlight and wind, it can be temporarily dispersed but reforms when fog conditions return.

It emerges during peak fog to disorient players with false paths and auditory illusions, escalating tension by representing the personal risk of possession and forcing adaptive strategies in low-visibility conditions.