Duel SIM: Strategy Board Game

Two players. One device. Draw lines — don't complete a triangle or you lose. Train with AI first, then face someone for real. Built on Ramsey Theory.

Duel SIM is part of the Duel series — games built around one idea: your phone as a board game. Two people, same room, one device between them. No online mode, no matchmaking, no notifications. Just the game and whoever's sitting across from you.

Not ready to face a real opponent yet? Two built-in AI modes let you train first — and show up prepared.

Duel SIM is a two-player abstract strategy game rooted in Ramsey Theory — the mathematical field that proves some patterns are unavoidable.

OBJECTIVE Players alternate drawing coloured lines between dots on a circular board. The player who completes a triangle in their own colour loses. Simple rule. Deep strategy.

GUARANTEED WINNER By Ramsey theory, on a board of 6 or more dots a single-colour triangle MUST eventually appear. The game always ends — stalemates are mathematically impossible.

GAME MODES • Local Duel — two players, one device, face to face • vs AI Trainer — hone your strategy against a heuristic opponent • vs AI Master — challenge the minimax engine for a serious fight

SETTINGS & DEPTH • Board size: 6, 7, 8 or 9 vertices — more dots means longer, more complex games • Partial Start — skip the quiet opening; jump straight into the tense endgame • Helper Lines — toggle available-move hints on or off • Match format — first player to reach a target score wins the match • Custom player names

CLEAN & FOCUSED No ads. No accounts. No internet required. Pick it up and play.

HOW TO PLAY Tap any dot, then tap another to draw a line in your colour. Avoid being the player who closes a triangle. Force your opponent into doing it instead.

A modern take on the classic pen-and-paper game of SIM, reimagined with neon visuals and a smooth touch interface. Part of the Duel series — turning phones back into board games.