"Repulsion" is a dexterity game in which, like Jenga, the object is to take turns building a tower and to try not to be the person who causes the tower to topple. In this game, though, the tower-building elements are six plastic spheres, with each sphere flattened at each of two ends. Inside the spheres at each end are magnets, so the magnetic fields generated by the sphere you're trying to place may repulse that of the sphere atop the tower (hence the game title, "Repulsion"), and so success in the game is dictated by your ability to delicately determine the polarities of your piece and that atop the tower without toppling the tower, and place your piece safely on top.