If you haven't already checked Scottgames.com recently, you will see that he has uploaded a new image featuring what seems to be Chica and the Infamous Cupcake. It bares the "Was it me?" slogan used from the previous teaser image that represented Bonnie, and uses the same message as the ones shown in the Freddy Teaser image as well as the Bonnie teaser image, which appears to state "Nightmare". She has many odd physical features such as a single glowing eye that shimmers red, three sets of teeth with the front rows being the sharpest of the bunch. Her head is also something to take a look at, as she has wires hanging out of her head and not only that, but Chica's head looks to be in a different shape rather than the occasional spherical shaped head we knew.
Getting onto different topics, the Cupcake makes a return and is sitting on Chica's shoulder as seen in the image and looks to be quite worn out and has a sharper set of teeth, perhaps the Cupcake will have an actual role in Five Nights 4, but we'll never know until Halloween.
From what I know, this image was published on Scottgames.com on May 16, 2015.