Note: This mini-expansion requires a copy of On the Underground: London / Berlin.

In The Underground Challenge, you will compete against the real Metro lines. The map starts with several lines already built, and you must try to surpass the Metro's score.

Like the engineering teams of London, you need to be quite resourceful in constructing railway lines, while simultaneously enticing passengers to use your lines instead of the official ones.

If you can outscore the Metro at its own game before the destination cards run out, you win The Underground Challenge!

Each round:

• Take four actions - each being either placing railway line tokens or taking branch tiles, as in the regular game.
• Perform passenger movement.
• Perform passenger movement again.

The passenger will thus visit one or two stations, and the destination cards corresponding to those stations will be removed and replaced as in the regular game.

The passenger will then visit another one or two stations, with the destination cards matching those stations being removed and replaced as well.

The passenger movement rules are the same as in the multiplayer game, with the following exceptions:

• If passenger movement is the player's choice (due to an equal number of empty spaces and lines involved in each possible route), the player must choose the route that gives the Metro the most points.
• If all possible routes would give the Metro and the player equal points, the player may choose any of those lines.

If your scoring tile reaches or exceeds the Metro's tile, the game ends and you have completed the Metro challenge!