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Stack a castle that stands
Castle ArchitectCastle Architect

Drag stones, slabs, arches, cone roofs and a wooden gate onto a storybook hill and build a castle that stands. Then press Test: a gust of wind leans on it and a friendly catapult lobs soft pumpkins at the walls.

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Genre
Physics building
Controls
  • Touch
  • Mouse
  • Keyboard
Devices
  • Desktop
  • Tablet
  • Mobile
Released
2026

Castle Architect

Castle Architect is a side-view building game on a storybook hillside, where the sky drifts from morning light to dusk. Pick blocks from the tray, stone squares, long slabs, arches, pillars, battlements, cone roofs, a wooden gate, a drawbridge plank and flags, and drag them onto the hill. Each one snaps to a fine grid, a ghost shows where it will land, and it settles under real physics: blocks rest on each other with friction, an overhang tips if it reaches too far, and a tall thin tower sways.

Press Test and the castle faces its trials. First a gust of wind leans on it for a few seconds, then a friendly catapult at the foot of the hill lobs a soft pumpkin that thumps against the walls and splats. Anything that falls just tumbles down the hill, and Back puts the build exactly as it was so you can shore it up. Forty brain-teasing challenges ask for a height, two towers either side of a gate, a roof over the royal bedroom, a bridge across the moat or a wall that survives three pumpkins, all within a block budget and without overloading the soft, muddy patches of the hill. Stand after the trials, stay under budget and lose no block for three stars.

Free build is the relaxing side: a wide hill, unlimited blocks, a day or dusk sky, wind and pumpkins whenever you call for them, a Photo button and room for twenty saved castles in your browser. Drag with a mouse or a finger, or use the keyboard: arrow keys move the cursor, Enter places, R rotates a slab and Space starts the test. Undo and redo go fifty steps back, and P pauses, M mutes.

Screenshots

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Castle Architect

Stack a castle that stands

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