staircase is part of:
    50%  stair

staircase contains:

Full expansion for staircase:
   100%  Belville 5-Step Straight Staircase
   100%  12x12x12 Quarter-Spiral Staircase
   100%  4x7x6 Open-Riser Staircase
   100%  6x6x9 Quarter-Spiral Staircase