The river Phlegethon, also known as the river of fire is located in the Underworld itself, and its liquid fire burns all it touches... and you must avoid it.
This storygame isn't very long, but theres a good amount of reading and branching. Technically, you can't really lose, but you can get a bad ending. That could count as losing if you want.
There are 13 endings, 5 bad, 3 good, 5 neutral. Good luck.