Sand Castle

The object of Sand Castle is to build a mountain 18 layers high. The player is given a lot of sand, a much smaller amount of gravel, and an even smaller amount of brick. In each turn, the player builds one layer of the mountain by choosing which material to use for that layer, and how wide to make the layer. When building a layer with sand, the layer needs to be at least 6 meters narrower than the layer beneath it. When building a layer with gravel, the layer needs to be at least 4 meters narrower than the layer beneath it. When building a layer with bricks, the layer needs to be at least 2 meters narrower than the layer beneath it.

The player wins the game if they can build all 18 layers. They lose the game either by running out of materials, or by not following one of the conditions outlined above (e.g., building a layer of sand which is less than 6 meters narrower than the layer beneath it), which will cause the mountain to collapse.