Let it go!
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This page contains details about Fallen London Actions.
Surely it won't know the way back to your lodgings? What harm will another rat do in Fallen London?
That sinking feeling
The rat scurries unerringly off towards your home like a mobile rodent compass. No doubt you'll be seeing it again. Whoops.
Success Instructions: You still have a rat problem at home. Return to your lodgings to face the little villains!