Whiffer Sniffers Mystery Pack 5 Scented Backpack Clip Whiffer Sniffers Series 2, Part 2 Scent lasts for up to a year. Only way to get Sunny Pop is in Mystery Pack 5 May get Sunny Pop or one of the other Series 2 regular Whiffer Sniffers. Gold Bags & Trading Card may also be found in Mystery Packs.