ナナイロアジサイ can be translated to “seven-colored hydrangea”.
In this Othello-esque game, players strive to change the color of a hydrangea to their own colors.
Depending on the amount of players, decide which colors will belong to each player. During a turn, players place a flower piece of one of their colors onto the hydrangea. When the hydrangea mat is completely covered in colored pieces, the game is over.
The player with the most flower pieces of their own colors on the hydrangea mat wins the game.
There are Color Transfer actions which allow players to change the colors of pieces already played onto the mat. For example, depending on the Color Rotation Chart, certain colors have established relationships. When placed next to each other, these colors will change based on the chart.
The placement rules guarantee the color of the hydrangea will be constantly in flux throughout the game.