Build a castle. Knock theirs down. Repeat until you rule the world.

Castle Stacker is a real-time siege game where your fortress falls from the sky one room at a time. Pick a card, line it up, drop it: a cannon here, a barracks there, a treasury tucked safely behind a rampart. Fill a whole row and the coffers ring with gold. Leave a gap and you'll be patching it under fire.

You don't fire the guns yourself. Your little people do. Bombardiers man the cannons, artificers scramble up ladders to mend cracked walls, guards hold the stairs, and soldiers gear up at the armoury and charge across no-man's-land. They're all after one man: the enemy king, who sits in his throne room and fights like two. Bring him down and his whole castle follows, room by room, in glorious slow motion.

A fortress is a puzzle with cannons in it

- Mage towers fire arcane bolts, ward stones raise shields, and storm spires chain lightning through raiders and balloons.

- Hot-air balloons drift overhead dropping trouble, mortar pits lob shells over the walls, and gargoyles guard your battlements.

- Bolt on drawbridges, crow's nests and grappling lines, then send your soldiers sliding straight into the enemy keep.

- Slip spies into their castle to sabotage it from the inside.

- Rooms stack, crumble and explode. One lucky shell on a foundry can take half a tower with it.

Conquer the Known World

Four realms, 33 territories and a warlord in every castle. Merchants out-earn you, Siege Gunners out-shoot you, Raiders flood the field, and Turtles hide behind their ramparts and taunt you. Each realm ends with a boss who has a move of their own: the Iron Tyrant's Iron Rain, the Drowned King's Undertow, the Ash Emperor's Firestorm, and the Sun Sultan's Mirage, which sends your gunners firing at empty sand. Knock a boss down to half health and find out what angry looks like.

Make the war your own

- Spend crowns in the War Council on permanent upgrades, new rooms and a deck built your way.

- Pick a doctrine before each battle: Iron Walls, Siege Masters, Merchant Princes, Vanguard or Master Builders.

- Call down royal decrees: Rally Cry, Artillery Barrage, Emergency Repairs, Smoke Screen and Hold the Walls.

- Claim one relic from each fallen boss's hoard. Choose wisely: the other two are gone for good.

- Answer petitions from your court. Hire mercenaries, tax a passing caravan, or gamble on ancient ruins.

No two battles alike

Eight battlefields, each with its own way of ruining your afternoon: lightning, earthquakes, blizzards, meteor showers, pirate broadsides, volcanic eruptions, sandstorms and flash floods, and they hit both sides alike. Supply balloons drop crates into no-man's-land for the fastest soldier to grab. Long sieges drift into dusk as the castle windows light up one by one.

And when you just want a fight

- Quick battles against four commanders, from Recruit to Warlord.

- A new daily challenge every day, with two rule twists.

- Replays of your last ten battles, at up to 8× speed.

Long live the king. Preferably yours.