Half Life 2: Dominion

The City 23 Citadel dominates the skyline, a monolithic dark tower of alien architecture piercing the clouds. Blue energy pulses visibly through its exterior, powering the city's suppression field and surveillance network. The structure serves as the Combine's nerve center, housing advanced teleportation technology connecting Earth to their interdimensional empire. At its apex sits Administrator Richter's Central Administration Complex, where he oversees city operations. Lower levels contain the Nova Prospekt detention wing where dissidents face interrogation or transformation into Stalkers. The Metropolitan Protection Force headquarters occupies mid-levels, with barracks, training facilities, and weaponry storage. The Citadel's base features heavily guarded access points where only authorized personnel may enter, while dropships and gunships regularly deploy from specialized hangars along its exterior.