Providing Entry and Exit points for a quick ambush and an equally quick get away; old drainage and sewage systems can provide a lot more hazard than a simple collapsed pipe.
Each player places D3-1 Manhole Cover Tokens in any open square on the 2nd and/or 3rd Tile. The squares with Manhole Cover Tokens count as Debris Squares.
On Foot characters may enter play from any square with a Manhole Cover Token.