Used by the routine at main.

The cauldron asks for fourteen objects in the order of the list at objects_required. This rotates that list left by 4 to 7 places, the number chosen by bits 0 and 1 of the game seed. The list itself never changes order, so every game asks for the same cycle of objects starting at a different point -- and since the list is in the game's code rather than its variables, the rotations add up from one game to the next.