Adding mystery eggs

[superdude44]

I really would like to have mystery eggs, (eggs which do not show it, only a description) then when they are adopted they reveal the type. However, after looking through some stuff it seems complicated and i do not know where to start. I am thinking maybe editing the adopt.php and save it as a new one, such as clever_name.php and then create a new page, or edit the front page, to redirect to this clever_name.php. the clever_name.php has the code to display the adoption page, but more so where it only displays the mystery eggs and then reveals them. would this work, or would i have to do more?

-thank you