The Battle of Ephyra was a major battle that took place ten years after Emergence Day (10 A.E.). It was a massive battle, with COG armed forces making a desperate stand to hold the city against tens of thousands of "Grubs" and Boomers, at least a thousand Reavers, and numerous amounts of Brumaks, Seeders and Corpsers. COG High Command and COGIntel originally thought that the Locust would have to travel across the surface from an area outside of the Jacinto Plateau in order to invade Ephyra. However, there was an unidentified fissure under the Jacinto Plateau that was only discovered just before the Locust began their assault.[citation needed] The Locust were able to penetrate through the surface and move through the metro stations and enter the city. The battle ended with the southern part