Mutated Energy Hounds began to surface when the Order of Mata Nui began to release Energy Hounds into the Pit. After a while in the Pit, some of the Energy Hounds began to change, and gained sentient qualities such as speech and the ability to walk upright, as well as brains with extremely complex decision-making capabilities. This allowed them to make decisions based on higher reasoning, and they began to rebel against their masters by abandoning their duties and attempting to live lives of their own.