Nuraf

Nuraf (also known as "Araf Nurikabe") combines the rules of Nurikabe and Araf puzzles. A rectangular or square grid contains numbers in some cells. The aim is to blacken some cells of a grid according to the following rules:

• The black cells divide the grid into areas of white cells ("islands").
• Cells with numbers are always white.
• Two islands may not be connected.
• All of the black cells must be connected.
• No 2 x 2 cell area within the grid can have the black color.
• Each island contains exactly two numbers. An island must have an area that is strictly between those numbers. For example, if the island contains 1 and 4, the island's area must be equal to 2 or 3.

Cross+A can solve puzzles from 3 x 3 to 30 x 30.