ravensburger gravitrax the game tThe Hammer action block is a challenging puzzle game that invites you to exercise your brain. With 30 challenge cards of varying difficulty, this game offers endless puzzling fun. The goal is to place all the pieces in the right place so the ball can roll from start to finish. Challenging puzzle game 30 assignment cards with different levels of difficulty Train your brain Place all parts in the right place Let the ball roll from start to finish