Battle of Genesis

The Battle of Genesis was a battle fought between UNSC Spartans, Servants of the Abiding Truth who replaced Jul 'Mdama's Covenant and the Promethean Created forces of Genesis in October 2558.

Prelude
After seeing a vision from his thought-to-be-deceased AI companion Cortana, Spartan-II John-117 headed to the planet Meridian with the rest of Blue Team to find her. Declared AWOL by the UNSC, Spartan-IV Fireteam Osiris led by Jameson Locke was sent to retrieve them. Osiris tracked Blue Team into an underground Forerunner structure and caught up with them but they managed to escape into a nearby Guardian. Osiris retreated as the Guardian entered slipspace over the planet.

The battle
After arriving on the Forerunner builder planet Genesis aboard the Guardian, Blue Team fought their way through Covenant forces who had crashed landed there. They eventually reached a structure where they encountered the Warden Eternal. The Warden revealed to them that he stood in defense of Cortana and proceeded to send Prometheans to stop the Spartans. After realizing the Prometheans couldn't stop them he engaged them himself, but was defeated. Blue Team was then contacted by Cortana who told them to enter the Domain and come to her so she could tell them her plans. Learning Cortana's goal is to uphold the Mantle of Responsibility John explained to the rest of Blue Team that the Mantle is a forced peace upon the galaxy, however Cortana assured them it wouldn't be like that. After fighting through the rest of the Promethean forces Blue Team entered the building that lead to the Domain.

Following closely behind them was Fireteam Osiris, who had arrived at Genesis on a Guardian from Sanghelios. With them was 031 Exuberant Witness, the monitor of the Genesis installation. After fighting through the battling forces of the Covenant and Prometheans, Osiris finally reached Blue Team's location, where they encountered two Wardens. After dispatching the Wardens, Osiris headed inside and offered to help Blue Team stop Cortana. Before they could do anything however, Blue Team was transported to the Domain, where they fought through Prometheans and three Wardens before finally reaching Cortana's location. John pleaded Cortana to come back with him, but Cortana refused and placed Blue Team inside a Cryptum. Learning what happened, Osiris moved to destroy the gravitational cores holding the Cryptum in place, while fighting Covenant and Promethean forces. After destroying the last core, Osiris followed Exuberant to the main core. Taking an elevator down, Osiris made there way to the core but were slowed down by a Guardians concussive blasts. Locke finally reached the core and destroyed it, but he was too late, Cortana had secured the Cryptum and was prepared to leave. However, before she could, Exuberant sent hundreds of Constructors who forced the Cryptum from the Guardians grasp just before it entered slipspace. The Constructors opened the Cryptum and Blue Team was reunited with Osiris, who promptly exfiltrated them.

List of appearances

 * Halo 5: Guardians