In this research, we develop an immersive mixed reality game environment using an actuated surface as a game stage. One game player creates the game environment by arranging tangible objects; those objects linearly flow and interact with a virtual character manipulated by another player. We expect that game enjoyment could be leveraged while being highly immersed into mixed reality game world. Also, new kinds of interaction between two players with different game roles are expected. The prototype was pilot-tested and planned for demonstration.