Phoenix Eggs are an item in Peggle Blast. They modify the environment by needing to be hatched. Phoenix Eggs have their own level type as well. In order to win these, the player must hatch all eggs. If even one drops off the screen, the player will lose. However, they can instantly hatch eggs if the Free Ball Bucket catches them first. 
Egg Level

A Phoenix Egg


These are the levels they appear in.