The Carpet and Claws
In season two, episode one (2.001, May the Giant Be With You ), Maddy Ferguson has a vision in the Palmer living room. The carpet near her chair rapidly becomes darkened by a stain or an effect called pooling, or sometimes watermarking, which happens when fibers are moved in an opposing direction. The reason I question if it is a stain is that claw marks seem to appear after the darkness has spread. Notice the marks intentionally raked across the carpet (Below).
