Conductor under lock and key

Exploration Stage: Room of Fate
From: Huntress
Description: What is that new monster?! My, it's a Fire breathing Mummy! You wouldn't lose this beastie at night, she's like a walking torch! She's blocked the entrance to the Station and she won't let anyone pass her. The poor Conductor was locked up at his place of work. Not only that, a City newcomer could come to the Station, unknowingly fall into the mummy's clutches and become grilled. I think I know what to do... Let's visit Martha - I'll tell you everything on the way.
Completed: The City is very logical, although not everyone will catch its logic. It's especially true for the interaction of elements and substances. For instance, the Iron Gargoyle can be banished with a magnet, the Fire Fury can be put out with water... The Fire Mummy probably fears water, too, but before we risk approaching it too closely, I'd like to seek Martha's advice.