Fortress

Build strength. Hold your ground.

Opponents

○ White player

■ Black player

Computer opponent · Black

Five distinct local opponents. Learning is optional after a finished game.

21 rounds. One tap to build. Strength up to three.

Independent rewrite · working title · rights unverified

○ White 0■ Black 0

Raster display unavailable. Use the complete accessible board.

Playable board

Arrows navigate. Enter/Space builds once. ○ White, ■ Black, · neutral. Numbers are strength.

At the table

Sound volume

Optional synthesized cues. Sound starts only when enabled here.

Rules & keyboard

Build on an empty cell or reinforce your own castle, up to strength 3. Enemy castles cannot be built on.

Influence adds the signed strengths of a cell and its four neighbors. Empty territory follows the stronger side. A castle collapses when opposing influence exceeds its support; collapses can cascade. Zero influence never collapses a castle.

After 21 rounds, the most controlled cells wins. Unavailable turns are skipped. White pixels and ○ labels are White; black pixels and ■ labels are Black. Strength adds a central keep and then its pointed crown. A closed doorway warns of opposing or zero net support. Flags mark controlled empty cells, never additional castles.

Opponent styles and optional local learning are independent modern reconstructions inspired by source analysis. Original personalities and numerical learning are not reproduced. Learning adjusts bounded preferences and may improve or worsen decisions. No cloud or account.

On the canvas or playable board: arrows navigate, Enter or Space builds immediately. Escape closes menus. Reduced motion is supported.

Fortress · 0.4.0 · local play

Start a fresh game?

This clears the board. Your opponents stay the same.

GAME OVER

Scores count controlled cells: castles plus flags. Neutral cells do not count.