Hex

Eight connection game variants across rhombus and triangular boards, with bridge-aware MCTS search, pie rule, and the same embed and SDK every family uses.

Embed via iframe

Every game family shares one embed surface. Select the family and variant through the URL.

<iframe
  src="https://engine.moddable.games/play/?embed=1&family=hex&variant=standard"
  style="width:100%;max-width:560px;aspect-ratio:1/1;border:none"
  title="Play Hex"
></iframe>

URL parameters

Param	Values	Default
`embed`	`1`	Required for embed mode
`family`	`hex`	`chess`
`variant`	Any variant key below	`standard`
`opponent`	`ai` \| `human`	`ai`
`difficulty`	`beginner` \| `easy` \| `medium` \| `hard` \| `expert`	`medium`
`theme`	Board theme id	`classic`

postMessage control

Commands accept either the generic game: prefix or the family prefix, so game:undo and hex:undo both work.

iframe.contentWindow.postMessage({ type: 'game:setVariant', variant: 'y-game' }, '*')
iframe.contentWindow.postMessage({ type: 'game:setDifficulty', difficulty: 'hard' }, '*')
iframe.contentWindow.postMessage({ type: 'game:newGame' }, '*')
iframe.contentWindow.postMessage({ type: 'game:undo' }, '*')
iframe.contentWindow.postMessage({ type: 'game:pass' }, '*')
iframe.contentWindow.postMessage({ type: 'game:resign' }, '*')
iframe.contentWindow.postMessage({ type: 'game:requestState' }, '*')

Events from embed

window.addEventListener('message', (e) => {
  switch (e.data.type) {
    case 'game:ready':  break  // { family, variant, state }
    case 'game:move':   break  // { move, state }
    case 'game:status': break  // { text, gameOver, family, variant }
    case 'game:state':  break  // { state } in reply to requestState
  }
})

Variants

All eight variants from the moddable-rules Hex hub are playable. Five are standard Hex on different board sizes; three are Y, played on a triangular board where both players must connect all three sides.

Key	Board	Distinguishing rule
`standard`	11×11 rhombus	Tournament size; connect opposite edges; pie rule
`9x9`	9×9 rhombus	Smaller board for faster games
`13x13`	13×13 rhombus	Larger board; deeper strategy
`14x14`	14×14 rhombus	International competition size
`19x19`	19×19 rhombus	Largest standard size
`y-game`	12-side triangle	Connect all 3 sides; both players share the same objective
`y-large`	16-side triangle	Larger Y board
`y-small`	8-side triangle	Compact Y board

Mechanics

The plugin is pure connection logic. All configuration arrives via frontmatter:

Config key	Effect
`connect`	`"edges"` (Hex: opposite pair) \| `"all-sides"` (Y: all three)
`pieRule`	After the first stone, second player may swap instead of replying
`shape`	`"rhombus"` \| `"triangle"`
`sideLength`	Board size (cells per edge)

No draws are possible on a hex grid. The search is MCTS with a bridge-aware rollout policy: if an opponent probes any bridge carrier, the defender always replies to maintain the connection.

SDK

import { createGame, createAI, listVariants } from 'moddable-engine/play'

listVariants('hex')                           // [{ key, label, group, board }]
const game = createGame('hex', 'standard')
game.applyMove({ action: 'place', to: '5,5' })

const ai = createAI('hex', 'standard', { difficulty: 'hard' })
ai.pickMove(game.getState().slice, 0)         // MCTS with bridge-aware rollouts