Sim
Six dots and two colours: join them with lines and do not close a triangle of your own colour — whoever does has lost.
Six dots in a circle and two pencils of different colours. Players take turns drawing , each in their own colour, and whoever first closes a loses.
A triangle counts by its corners only: three dots joined pairwise by lines of one colour. Where chords cross in the middle of the drawing means nothing, and that is the first thing to get used to — the picture thickens quickly, and only the dots are worth looking at.
There are fifteen chords in all, and therein lies the game: avoiding a triangle to the end is impossible. However fifteen lines are painted in two colours, a one-coloured triangle must appear — so Sim has no draws, and a game always ends in somebody's defeat.
Rules of Sim
The field
Six dots set out in a circle — usually the corners of a regular hexagon, so that every pair is equally visible.
Each player takes a colour.
A turn
The player draws one line of their colour between any two dots not yet joined.
Passing is not allowed. A line drawn is neither recoloured nor rubbed out.
Losing
The loser is whoever closes a triangle of their own colour with their move — that is, joins three dots pairwise in one colour.
Triangles made of lines of different colours mean nothing, as do the points where chords cross.
End of the game
The game ends the moment somebody's triangle closes. Reaching the end without closing one is impossible, so the game has no draws.
Worth knowing
A colourless description is also met: the lines are shared, and the forbidden move is one after which any three dots stand joined pairwise. That is a different game — there the player with nothing to draw loses — and the two should not be confused. More than six dots are sometimes used, but the game then runs long and loses the property that makes it what it is.
Glossary of terms
- A chord
- A line between two of the six dots. There are fifteen of them, and each is drawn once.
- Your own triangle
- Three dots joined pairwise by lines of one colour. Whoever draws the last of them loses.