Created by Mata Nui, Petrosaurians were made to inhabit the rocky isle of Terrasauria. Here, they lived in relative peace, mining rock and minerals as a source of food. They eventually discovered, however, that other lands in the world would pay handsomely for the various rare stones and minerals found on Terrasauria, which lead to the Petrosaurians becoming a significant and successful mining power within the Matoran Universe.