Build a fortress-city, explore a dangerous wilderness, and hold against increasingly deadly Monster Tides. The Citadel Must Hold is a base-building survival RTS where pausable real-time battles, hero-led exploration, and powerful choices shape every run.

Grow a settlement around the Citadel heart. Secure resources, expand production, train soldiers, and surround your city with walls, gates, and defense towers. Every expansion makes you stronger, but gives you more ground to protect.

Send your hero into the fog-covered wilderness between Monster Tides. Discover valuable resources and mysterious Places of Power, defeat their guardians, and choose your reward. Each Place of Power offers different rewards - some grant monsters that fight for you, some strengthen your hero, army, or buildings, and some reshape the map itself.

Between Tides the world is calm: build, explore, and prepare for the coming Tide. Position your hero and soldiers at critical chokepoints, garrison your towers, reinforce threatened walls.

Then the horns sound and the wilderness descends upon your gates. Every Tide is larger and more dangerous than the last. Pause the battle to assess the field, issue orders, and respond when monsters break through. Adapt when your defenses fail, and hold the Citadel against everything the world sends at it.

Begin each game by choosing a Founding Oath that changes what you can build and how you fight. Make your hero legendary, but give up the ability to train other units. Empower your army, but abandon walls entirely. Or choose a less restrictive blessing and build around its strengths.

After every Monster Tide you survive, select a Rally Decree to reinforce your strategy, cover a weakness, or transform how your forces fight.