Alright this is my first post and so forgive me if this has been proposed before. In a recent reread of Mistborn era 1 I realized that in many of the references to the Deepness, it referenced it as being dark or black. However during the Final Empire and after, the Mists are white. The Mists are of Preservation, but could the Deepness have been something like Ruin’s “Mist”? Because Ruin’s power is frequently black. His Shardpool is black. They see his power as a black smoke.