The Den of Evil - Wicked Addition Set contains these pieces:

1x 6" Straight Wall and Archway
1x 4" x 4" Raised Platform w/Removable Lid
2x 6" x 6" Floor Tiles w/Gem Insert
4x Curved Corners
4x Curved Corner Floor Tiles
4x Stone Pillars
2x 2" x 2" Floor Tile w/Stairs Down
2x Upper and Lower Stairs
4x Tentacle Pillars