The Wicked Streets Pack is part of the City Builder System. The Wicked Streets Pack is made of "Dwarvenite". The Wicked Streets was initially available as Add-On item during the City Builder System Kickstarter. The item comes in both painted and unpainted versions.
The Wicked Streets Pack comes with these 8 pieces:
(4) Street, Straight, Nobles' Crossing, 4x4
(2) Street, Straight, Sewer Drain, 4x4
(2) Street Straight, Sewer Grate, 4x4