The Subway

The Subway is the second chapter of the first campaign, No Mercy. As of the demo, only the first half of this map is available: it consists of going through a subway station and tunnels, coming out through a generator room, then surfacing through a building. In the full game, however, another small area of the map is accessible, consisting of the survivors emerging from the building in an attempt to reach a pawn shop at the end of an urban street. This area is still accessible in the demo via the "noclip" console command, but the AI director will not generate enemies in the area, nor is there any safe room to reach.

Tactics
Smoker: At the end of the level, there's a street containing a car with an alarm ready to go off. Stand behind this car, and pull a survivor over the car to set off the alarm and alert the horde. This should make things much easier.

Tank: At the end of the level, there's a street containing a car with an alarm ready to go off. Hit this car at the survivors for an instant incap. If an incapped survivor is hit by the moving car, it's instant death.

 Hunter/Boomer: An Infected can push the piano in the pawn shop into the safe room doorway, preventing the survivors from entering.

Trivia

 * there is a Safety Checklist In the safe room at the end of the chapter a checklist of safety instructions can be found. It is a poster that is produced by CEDA which is believed to be a company connected to the infection.
 * The 3rd item has been crossed out and labeled with the words Not Airborne which implies that initially the virus was thought to be airborne but the theory was later disproved.
 * Seek shelter in fortified, windowless room, preferably underground.
 * Ensure all openings have been securely obstructed.
 * Secure the room with plastic sheeting and duct tape.
 * Listen to your radio for further instructions from authorities.
 * there is an Easter Egg in the subway near one of the escalators, there is a poster of the "Orange Box" juice.
 * The Crescendo Event in the power room is avoidable by means of Charging the Minigun.