extreme-slope is part of:
    50%  slope

extreme-slope contains:

Full expansion for extreme-slope:
   100%  1x2x3 Extreme-Slope Brick
   100%  1x2x3 Inverse-Extreme-Slope Brick
   100%  2x2x3 Extreme-Slope Brick
   100%  2x2x3 Extreme-Slope ConvexCorner Brick
    80%  2x2x2 Extreme-Slope Brick w/ CenterStud
    50%  6x4x6 Staired Sloped Wall, Jackal Decor
    50%  6x4x6 Staired Sloped Wall, Owl Decor
    50%  6x4x6 Staired Sloped Wall