Siege of the Inner Colonies
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Outer Colony slaughters
From June 1, 2536 onwards, the Covenant would press into the Inner Colonies.
Eight years afterward, the Inner Colony of Miridem would fall to the Covenant. This would eventually result in the capture of Catherine Halsey. In May 2545, Actium was discovered by the Covenant, resulting in the month long Battle of Actium.
Attacks in the Epsilon Eridani system
Fighting in the Sol System
The Lesser Ark
The joint UNSC and Sangheili forces were deployed to the Ark after discovering the portal.