What about making the areas of you collect... er, whatever you collect, unpassable when the snake has moved off them. That way, you need to plan more which areas your snake goes to.
The only way to keep the area from becoming un-passable, is to keep the snake somewhere on that area. It would probably be better making larger slabs though, in stead of tiny squares being unpassable.
The only way to keep the area from becoming un-passable, is to keep the snake somewhere on that area. It would probably be better making larger slabs though, in stead of tiny squares being unpassable.