Combiku™ rules are very simple.

You are given a 5x5 board which contains some numbers and letters on it.

Use the mouse to drag other Numbers or Letters from the sides into the board
squares.

Your objective is to place one Number and one Letter in each square.
 Two squares cannot have the same combination NumberLetter.
 And a Number (or Letter) cannot be repeated in the same column (or row).

You may prefer to use Shapes and Colors
instead of Numbers and Letters.
Don't hesitate to use the following features:

Save a puzzle to resume it later.

Let the computer play for you and explain the move.

UndoRedo your movements.

Display little notes on each square to keep track of your own conclusions.

Switch between "Numbers and Letters" and "Shapes and Colors".

Highlight the first square with a mistake with respect to the puzzle solution.
Combiku puzzles are rated from 1 to 5 stars (5 being the hardest). All puzzles have one and only one solution.
