Some time during the Second Age, humans living on Ymir figured out how to use adonium to create their own automatons to assist in mining adonium. Rather than running on electricity, these automatons ran on the magic of adonium itself. Every automaton has an adonium core, which acts as the seat of its consciousness. However, not every automaton has free will or total consciousness. Many simply behave as their makers programmed them to behave.

Most of the humans of Ymir live in the various nations of the world. While their primary purpose is mining, the majority of humans do not mine, but rather spend their time supporting the mining operations in a number of ways. Some grow food on farms, some cut wood in the forests, others travel across the known world trading goods, etc. Whatever their professions, they are most often paid in seleni coins, of which they are expected to give half to the local temple.