This game belongs to a series of 4 games by Scandecor, who come in a square plastic box (Play Cavalry, Play Balance, Play Ecology and Play Numeric).
Play Ecology looks like a mixture of "Trap the Cap" and "Chess", but it is not as easy as that sounds. Each of the players has 6 playing pieces, which move like the Knights in chess. In the middle of the board is one neutral piece, who carries a wooden ball on his crater shaped top.
Object of the game is to catch that wooden ball (the playing pieces all have small craters on their top to put the ball on top) and bring it to your edge of the 9x9 game board. The neutral piece moves like the king in chess and it can make captures by jumping on other pieces - like in "Trap the Cap". What makes the game interesting is, that the neutral piece is the only piece that can capture normal pieces. That means, that you need at least 1 piece to capture the ball, but the other pieces can only try to block other pieces from doing so.