Game piece in the form of a polyomino or polycube or similar, consisting of a number of blocks (5) that are put together in an orthogonal pattern, characterized in that the game piece (4) comprises at least two parts (6) that are each formed by a number of aforementioned blocks (5) connected together in a fixed way, whereby these parts (6) are slidably coupled with respect to one another in such a way that they enable a number of forms of game pieces (4) to be formed with the game piece (4) concerned.