The Battle of KLV-479 was one of the bloodiest battles that the 1st infantry division of the UNSC Army would ever fight. They are completely cut off from the rest of the covenant with only pockets of reinforcements showing for time to time to help reinforce there positions and the Navy barely holding the Covenants task force from obliterating there's. They suffered over 75% casualties and would never be considered back to full strength cause they are immediately called back to earth to defend the city of Seattle