The Citadel is a labyrinth of Combine architecture. You'll encounter new Combine units, including Combine Advisors (though you won't fight them directly yet) and various automated defenses. Your objective is to reach Dr. Breen's office at the top. You'll need to solve environmental puzzles involving energy fields, force barriers, and moving platforms, all while fending off relentless Combine attacks. The supercharged Gravity Gun makes these encounters manageable, but you still need to be strategic. You'll eventually reach the top, where the final confrontation awaits.
Half-Life 2
Citadel Infiltration
Master Citadel Infiltration in Half-Life 2. Use the Gravity Gun to navigate Combine architecture, overcome energy fields, and reach Dr. Breen.