Two players, one screen

Play head to head on this one screen — or play both sides yourself to see how it works. Put your names in, toss for who starts, then take turns.

The puzzle

Every triangle's centre number is the sum of its three edges, and where two triangles meet the number on the shared edge is the same for both. The key down the side lists the number-triplets you place. You work it out by logic — never by guessing.

Taking a turn

Click the triplet box you want — say 000 — and a floating triangle appears. Put it the right way up (pull the apex up or down), drag the numbers into the right positions, then drag the triangle over the place on the board where you want it. When you’re happy, press Ink and the turn passes to your opponent.

Right → +1 point. Wrong → −1 point, and the other player chooses: You Go Again (you keep trying) or I Go Next (they take over).

The clock is the catch

Each turn is timed. Under the clock it is tempting to guess — and a guess can cost you a point. Keeping your nerve is how you win.

If a player is timed out, the game stops and that player loses a point. The opponent can either put them back in or take the turn themselves. Remembering an opponent’s error can be a good tactical advantage.

Winning

When every triangle is filled, whoever has the most points wins.

The full Trigon Duel pits you against other players online, on a leaderboard.