Draco ovum
 
"The dragon protects its egg by nesting in the heart of a dormant volcano. The soft and constant warmth will keep the egg at an optimal temperature before it can hatch. Once the time comes for the baby dragon to hatch,the dragonness will pour scortching hot lava directly onto the egg. After cooling, it will take one to two weeks for the young dragon to pierce the external shell created by the heat."