Free Transformers Puzzle Pack
This is 3 in 1 Transformer puzzle pack: swap, spin and clear. Each puzzle comes in three different levels of hardness. Underlying image gets randomized each time you start a puzzle, so you basically never get to play identical game, which is nice.
In 'swap' puzzle, the underlying image is divided into several rows and columns, which form together a matrix of movable blocks. The restriction is that you are allowed to move only one block at a time, i.e. to swap two successive blocks. By slowly moving blocks you complete the picture and solve the puzzle. The number of blocks of course is determined by the chosen hardness level, logically.
Unlike 'swap', spin puzzles are less common. I know they exist it's just that I really rarely see them in games. In this case, an image is devided into rings. By unscrambling the rings you solve the puzzle. Click and rotate individual rings to make them rotate around the center, until everything locked into correct place. It's not really much harder than a swap puzzle. You can always click 'hint' button to check what are you trying to archive.
In 'clear' variant of the puzzle you are using shapes to clear out the grey blocks. Optionally you may rotate each shape by a mouse wheel or with the space bar. You may also delete current shape by using the trash can from the bottom left corner. Once you clear all the grey, the game is completed. Very interesting variation of a puzzle game as it resembles to Tetris. I've noticed that mouse wheel works but the space button does not. Actually this type of puzzle is maybe even the easiest because you may use delete function as much as you like. So you are basically allowed to delete as much shapes as you want until you get the want you want, which makes this version probably the least challenging.