Eggs

Eggs will be the result of Breeding Pets.

Overview
When the player breeds a pet with another pet, one of the pets lays an egg. This egg contains a merge of the parent pets, and it takes time to hatch. The egg's appearance will be based off the element(s) the parents use. When it first hatches, it starts at Level 1. Level 100 parent pets' eggs will hatch at Level 20. Each evolution level will be based off the levels the parents evolved at.

Improving Gameplay
If pets are breed, this could contribute to the trading idea. Players can trade rare pets that result of breeding for other items. Also, there could be a randomness factor put in, making the hatchling have a unique status (Rare, Heroic, Common, etc). They can also make it so that players could trade the eggs themselves.

Math Factor
In order for a higher chance for there to be a successful breeding, you have to answer math questions correctly. The more questions answered correctly, the higher chance of eggs. This could also affect the number of eggs.

Gallery
You may add concept sketches and drawings of Eggs here, but make sure to request permission from the original artist and credit them, and follow any rules they have for use of the image.