There are a few neons that are not available in adopt me! As Neon pets get deleted over time, some stay relatively long while others disappear faster. For example, the Pet Rock was only available for a certain amount of time and then eventually disappeared. The Chick and Pumpkin (Pet) neons were limited and as such were deleted after a certain number of uses. So, while it is possible to create neons with these items, they may not be as brightly coloured or have all of the features of a standard neon pet.