1.Design a situation.under this situation, all moveable objects must be on certain squares.
2.When your tank reach this situation, you have to use bricks to stop sliding on ice/movers(because moveable pieces cannot leave their places).
3.So, before this situation, Bricks have no difference from solid blocks.
4.And those "solid blocks" cause much trouble for you to move the moveable objects to their destinies.
Now I am making a level using this idea. But the level is not easy to design:-)
bye,
lyf