Montrose committed his reserves, a force of Gordon infantry, and the Covenant forces broke.

The first novel begins as Covenant forces attack the planet Reach and vitrify the surface, turning its landmasses into glass.

The player must fight through Covenant forces to disable the bombs.

Buck makes a rough landing after the drop and fights through Covenant forces to find Dare.

After fighting Covenant forces, Ruwan and Tyla are rescued by marines and leave the city.

The player and the marines fight their way through invading Covenant force to a human outpost.

Forge's troops defeat the Covenant forces before they can destroy the installation, and Anders arrives.

Noble Team, dispatched to discover why a communications relay has gone offline, discovers Covenant forces on Reach.

Halsey informs Noble Team that the Covenant forces at the relay were searching for important information.

The post-credits scene puts the player in control of Six's last stand against overwhelming Covenant forces.