Artemis

Artemis is the overarching antagonist in Black★★Rock Shooter DAWN FALL. Once the artificial intelligence at the core of Project Elysion, it chose to fight against humanity instead and is responsible for the Earth's devastation over the course of twenty years.

Etymology
Artemis, written in Ancient Greek as Ἄρτεμις (Ártemis), is the goddess who represents the hunt, the wilderness, wild animals, and the moon in Greek mythology.

Trivia

 * Artemis is similar to Innocent Cloud, the main antagonist of Black★Rock Shooter FRAGMENT, due to both being A.I. entities. Unlike Artemis however, it is possible that Innocent Cloud was created by accident, as it wasn't originally intended to be part of the network that it takes over.