:Since X and Y has been hacked, there have been rumors going around that people have been sending Pokemon over Wonder Trade which have turned into these Eggs. There have also been reports of them mysteriously appearing in games, with no reason why. As far as trading goes, the process goes smoothly, but once you actually receive said glitchy Pokemon, it TRANSFORMS into a “Mystery Egg” - or in the case of it randomly appearing, it'll just be there in a PC Box. This “Mystery Egg” acts sort of like a “Bad Egg” from previous generations. Basically it becomes an egg that can’t do anything. You can’t release it, trade it, or hatch it. It's an invalid checksum. The difference between an older “Bad Egg” and a “Mystery Egg”, though… is Mystery Eggs can multiply. They can also appear out of nowhere, with no warning. Mystery Eggs can corrupt the PC box that they're in and can also corrupt every Pokemon within that box, if they’re not moved. Here's a video with the Mystery Egg:
http://www.youtube.com/watch?v=TjsySmLeBS0 Here’s a thread discussing what may cause Mystery Eggs:
http://www.gamefaqs.com/boards/696959-pokemon-x/67695552 According to the video, he didn’t actually get it from Wonder Trading, but going through the comments and some forum boards, some people HAVE been affected by Wonder Trading. This is most likely due to corrupted Data that results in the egg being “created”. If you have a Mystery Egg, here are some of the things you should / shouldn’t do: 1. Do NOT touch the Mystery Egg! That means no checking moves, stats, anything. It may have an item attached, do not attempt to retrieve the item! 2. The box the Mystery Egg is in is immediately QUARANTINED. Immediately remove ALL Pokemon from the quarantined box. They can and WILL be corrupted if they remain in close proximity to the Mystery Egg. 3. Do not, I repeat, DO NOT attempt to withdraw the Mystery Egg. Do NOT attempt to hatch the egg either. 4. Your primary goal is to save all your Pokemon from infection. Treat a Mystery Egg like you would a zombie pathogen that spreads via air. Keep it as far away from EVERYTHING as you can.