WordChess

Build words by placing letter tiles from your rack onto a large 25×25 grid. Each new word has to connect to tiles already on the board, and special squares scattered across the grid multiply letter or word values, so where you play matters as much as what you play. Score the most points by the end of the game to win.

• Form words across or down; every play must link to existing tiles.
• Land letters on premium squares to multiply your score, and chase long-word bonuses.
• Play against the computer, share one device with friends, or face opponents online.
• Optional specialty and profession word lists tilt the vocabulary toward different themes.

• Desktop: click a tile in your rack and click a board square to place it; submit your word when the play is ready.
• Phone & tablet: fully touch-friendly, tap to pick up and place tiles and to confirm your turn.

• Versus computer: choose opponent difficulty from easy through normal, hard and grandmaster.
• Pass-and-play: take turns on a single device with friends or family.
• Online: connect with other players for a live match (supports two to four seats).

• Hold high-value letters until a multiplier square is in reach instead of dumping them early.
• Open new lines that branch off existing words so you have somewhere to build next turn.
• Block premium squares from opponents when you can't use them yourself.
• On the big board, plan two moves ahead, space is plentiful, but tempo wins.

Premium squares scattered across the grid multiply your score, land letters on them to make a play pay off:

• Gray: normal square (no bonus).
• Cyan: Double Letter Score (DLS), doubles that letter's value.
• Blue: Triple Letter Score (TLS), triples that letter's value.
• Pink: Double Word Score (DWS), doubles the whole word.
• Red: Triple Word Score (TWS), triples the whole word.
• Purple star: the starting square (also a Double Word Score).

Laying letter tiles from a rack to build interlocking words on a premium-square grid is Scrabble, invented in 1931 by the American architect Alfred Mosher Butts, and behind it the crossword, whose modern form was popularised by the New York World in the 1910s.

The original change is scale: a 25×25 board rather than 15×15.

Board size is not a cosmetic choice in a tile game. Scrabble's tightness comes from a small grid where good squares are contested and the board closes up; a much larger one keeps openings available far longer, so play stays about construction rather than about denying the last bonus square.

WordChess is an original tile-laying word strategy game built in-house. It reimagines crossword-style word building on an extra-large grid with smart AI opponents, pass-and-play, and online matches, free to play in your browser.

A free, original browser game on PlayPendium. No download, no install.

1. How a computer picks a word

   Before the AI plays, it must find its move inside a haystack of a hundred and fifty thousand words, and then stop looking.
2. Teaching a machine 149,000 words, in 22 languages

   A word game needs more than a list of legal strings. It needs to say what each one means, and meaning is the hardest thing to store.
3. The Game With No Bad Draws

   Take the bag away from a word game and something disappears with it, the alibi, the miracle, and the whole drama of luck.
4. The Mathematics of a Letter

   Q is worth ten points and E is worth one. That single fact hides a small theory of language, an argument about information, and a reason the game's tile set looks different in Spanish than in English.
5. A Combinatorial Ocean

   Chess is our benchmark for depth. A quiet design choice gives WordChess a far larger space of possible games.