RENTEN

You strategically move one of the 15 pieces on the 16 cells to empty cell to start the artistic and theoretical drive on the cells and to make the back color black from white as much as possible according to the unique chain reaction system.
(1)1 game consists of 10 rounds with three shots each.
(2) Your objective is to make the total score as big as possible.
(3) When you hit three shots or you make all 16 cells black, the next round will begin with all cells returning to white.
The structure of the piece and how to play＆drive
(1)A piece is divided into 4 sectors and shows the number of 0-3 respectively. The red sector is called Activation Point. When you freely move one piece onto the blank cell, the piece which is facing the Activation Point will rotate counterclockwise according to the number on the Activation Point
(2)And the rotation starts chain reaction toward the direction indicated by the Activation Point of the originally moved and put piece.
(3)The second next piece on the direction will rotate as well according to the number of the contacting sector of the first rotating piece, and the drive lasts continuously up to 10.
(4)If the number on the sector of rotated piece is zero or the drive runs into the blank cell or the wall, the direction will turn to the left. If the left direction is also the blank or the wall, the drive ends.
(5)Only at the 3rd shot, if the 10th drive ends with activation point facing upper side, the drive extends up to further 20 as Extension, which can lead you the higher and exciting score!
The score calculation
(1)When 16 cells are all blacked completely in the round, you can gain 1600 point as all cleared bonus. Also you can get the additional point as multiply the square of the number of drives, and the number of the blacked cell in the last shot.
(2)When you fail to black all cells completely in the round, you get only the number of black cells × 50 points