Top Secret bonus level:
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Play level 6, „Metro Mayhem”. During that level you will reach a
station with an arcade. Get on the train at this station. Stand at
the door and wait for a darkened station blocked by a gate to pass
by. Note: Stay on the train if you miss it. Jump off the train at
the darkened station, then search for a hole in the gate toward the
left. Once in the station, look for two vending machines. Blow up
the crack in the wall with explosives and enter. Move through the
bathroom and the infested train car. You can find the secret exit
to the „Top Secret” level at the end of the broken train car’s track.
