The Blue Egg is an exclusive egg that was only available at the very start of the Pets Update in Adopt Me! It costs 100 bucks, and can/could only hatch into an Uncommon Blue Dog. Another similar egg that came out, was the Pink egg that could only hatch into a Pink Cat. Most players believe it is rarer than a Pink Egg. Although it could only hatch an uncommon, it is rarer now because it is unavailable to get. Some say it is worth a Neon Blue Dog.