If you've ever been to the Shinjuku train station, you know how huge and confusing it is. Even Tokyoites who use the station every day of their lives can get lost there. Once, Carla and I got lost in a quiet part of Shinjuku where there were almost no other people in sight, and it felt like this new game on Steam called The Exit 8.
From the game's Steam page:
You are trapped in an endless underground passageway.
Take a good look around and find a way to escape.
Don't overlook any anomalies.
If you find anomalies, turn around immediately.
If you don't find anomalies, do not turn back.
To go out from Exit 8.
The good news is the play time is just 15-30 minutes. The not-as-good news is it's Windows only.