Using the Rusty chest on Wizard Rinsit in the Wizards' Tower will prompt the player to ask for help unlocking it, which he will do, allowing the player to get the Magical feather.
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Wizard Rinsit is most likely a reference to Rincewind the Wizard, a character from the Discworld novel series by Sir Terry Pratchett. Both being described as being 'young'; as well as Rinsit having a having a resemblance to Rincewind from the TV adaptation of "The Colour of Magic".