Rat Catcher's Flute
Rat Catcher's Flute as a quest objective
Five Enthralled Deeprun Rats, created by using the flute on five Deeprun Rats, are the other objective of the quest.
The Rat Catcher's Flute has limited range. You must be close to the rats in order to use it on them.
The Rat Catcher's Flute has a casting time of around a second. A rat running away from you when you start will be out of range before you finish, and the Enthrallment will fail. Use it on rats that are approaching you or have paused running.
You can tame as many Deeprun Rats as you want to with this item; there is no limit (or it is high enough that no one has found it).
The Rat Catcher's Flute only works on Deeprun Rats.
The Rat Catcher's Flute disappears when you turn the quest in.
It might be an item to hang on to to tame Deeprun Rats at will, but the Enthralled Deeprun Rats disappear if you exit the Deeprun Tram instance.
The Rat Catcher's Flute and quest is an homage to The Pied Piper of Hamelin.