Choose the 4 colors that you will use in your game :

Choose the number of boxes the game should have :

Congratulations! You have successfully filled the Ran-gi Board!

Oops! The board is not correctly filled. Choose one of the following :

Instructions for Ran-gi

Introduction

Welcome to Ran-gi!

Ran-gi is a fun logic-based puzzle game for the whole family and the classroom.

The puzzle consists of 100 (or 81, or 64 or 49) squares arranged in a grid. The aim of the game is to colour all the white squares according to the rules given below. There are 4 colours on the board. A puzzle can have only one correct solution.

The rules

Figure A is an incomplete 10 by 10 Ran-gi puzzle, and Figure B is the same puzzle after being correctly filled.

An unfilled Ran-gi board.
Figure A
A filled Ran-gi board.
Figure B

The squares in Figure B are arranged in strips of one or more squares aligned either vertically or horizontally, and sharing the same colour. Unless they are in the same strip, squares that are the same colour are not related.

The square or squares that make up a group cannot be of the same colour as any square that directly neighbours any of them. This is illustrated in Figure C. The squares marked with letter "X" cannot be yellow, since each of them shares a side with a yellow square. The squares marked with ticks: "✓" can be legally yellow since they are not direct neighbours of any of the yellow squares.

Figure C

Groups of the same colour cannot intersect, or touch each other directly. A group forms an island of its colour within its vicinity.

The clues

A square with a colour C and a number N indicates that that square is a member of a group of N squares that are all of colour C. This type of square cannot be filled.

A white square with a number N inside it is a member of a group of N squares whose colour you will deduce. This type of square can be filled.

A square of colour C that has no number inside it indicates that that square is a member of a strip of that colour. This type of square cannot be filled.

A square with neither colour nor number offers no information. This type of square can be filled.

If a square has a dot "•", that square is a pre-filled colour clue, and you will not be able to change its colour.

Clicking on white squares will cause them to change colour according to the palette currently in use. Click until the square turns white to revert it to white.

When you have filled the board, i.e there are no more white squares, click "Is it Correct?" to validate your answers.