Empyra is the city where most of the action takes place in Gears of War. The Alpha and Delta squads were both sent into the city to set the resonator inside the Locust tunnels, a mission which turned out all to be in vein as the resonator did not acquire as much information as was hoped.
Ephyra was the Capital of both the Coalition and the nation of Tyran during the Pendulum wars. The Lightmass Bombing took place in the city of Ephyra. It is built upon the once-thought impregnable Jacinto Plateau by the COG, Ephyra is now infested and overrun by the Locust and only a few pockets of Stranded human survivors remain. Now in ruin, every night after dusk, the city becomes the feeding ground of the fearsome and indiscriminate Kryll, and all who live there must ensure that their location is well lit or they will fall prey to the ferocious creatures. The members of Alpha and Delta Squad were both sent into Ephyra to place the resonator in the Locust tunnels. However, when that failed, Delta Squad headed for Tyro Station to catch a train to activate the Lightmass Bomb.