GAME: Puzzle 15
The objective of the game is to move the squares so they stand in the order from 1 to 15 starting upper-left corner from left to right ending with the empty square in the bottom right corner.
When the game is started or the "restart" button clicked the squares are placed with "no order". The game has a score result. The result depends on the time a player needed to complete the puzzle and the number of clicks made. The time starts with the first click. The more time elapsed and the more clicks were done - the less is the score.
*you may want to think over your first several moves. Thus you will save time and clicks.
This is the initial position of the game. Every time it's different.
You can move only the squares which are directly on the left, right, above or under the empty square. Diagonals do not work. When a square is clicked it switches its position with the empty square.
The 5 is clicked. It moves to the right, while the empty square moves to the left.
Now after this move numbers 8, 3, 11 and 5 (again) are available for an exchange. In other words, you just clear the space for a square to move. It's easy. Just try.
After you solved the puzzle, the squares will disappear letting you see the whole picture, and alert will pop-up with your score and seconds needed to solve the puzzle. After that you will be redirected to the high scores table. If your result is better than any 10 records set before, you will be able to leave your name and comment in the high scores table.
And one more detail.
This puzzle has a so called bug. It's proven mathematically that if you use simple random method for dealing the squares (the one used here) it is not always possible to solve the puzzle. I intensionally used this simple randomizer to make it more fun. :)
 
Good luck!