In order to get the halloween dog snapchat lens filter you will simply activate the snapchat lenses the same way you always have. Next you will scroll to the dog snapchat lens. You will notice that the icon for the dog snapchat lens looks a little different. Instead of having black eyes, it has red eyes. When you select the dog snapchat lens you will notice an orange icon with a pumpkin right above the dog filter icon. This is the icon for the Halloween Dog snapchat lens. In order to use the Halloween dog snapchat lens filter, you simply tap anywhere on the screen like you are focusing the camera. This will apply the halloween effect on the dog snapchat lens/filter.