Number Island

Each board, whatever difficulty, has the same goal: you need to make number islands that match total the targets you have.

As you click cells on the main board, they are highlighted in grey. As you click more, you can create islands of numbers that are joined horizontally and vertically.

When the total of your island matches a target, both the island and target are highlighted blue.

Keep going until you have created an island for each of your target numbers.