What's wrong with this egg?

[Cardiac]

Double yolk, but the shell wasn't fully formed. Was cracked and pushed in at the tip. Cracked it open to see anyway, and this came out.

 

[Spiderduck]

Never seen that before!
Hopefully someone knows
But i wouldnt eat that egg if i were you

 

[coach723]

It looks like a malformed shell inside the egg. If its a young bird just coming into lay, or an older bird coming back into lay, you can have glitches on occasion while their system gets back on track. New layers are the most common to find double yolks in, but some birds are more prone than others. I would just keep an eye on this bird and make sure that it doesn't become a regular thing. Any kind of stress can cause glitches in laying and egg formation also. Hopefully it will straighten out on its own.