Orion IVEditThe planet of OrionIV, used to be a peaceful planet until a great revolt lead to the capital's downfall. Many Men, Women, and children were killed during this revolt. The master minds behind it were the rebel group Black Delta.
ReinforcementsEditThousands of UNSC troops were called in to help the revolt but Black Delta was too strong. The UNSC then called for heavy weapons including 2 Marathon Class Cruisers, 10 Frigates, and 15 Spartan-IV's. Among the Spartans was Fireteam Saber. Eventually, the rebels became overwhelmed by the Spartans and fled. But after they left, and even bigger threat arrived.
After the rebels left, Covenant carriers and cruisers came out of slip space. Even more UNSC reinforcements were called in. Outgunned and outnumbered, the UNSC eventually retreated to saftey.
When the UNSC became overrun, they ordered all units in the are to retreat. The covenant then later glassed the whole city leaving no survivors, including the covenants own troops that didn't make it.