Seafarer's Quill

This elegant swan feather quill has a solid gold nib that allows you to write in perfect cursive, granting an expertise die on any forgery kit check you make as long as the handwriting you are copying is also in cursive.

Strangely enough, you can use a bonus action or reaction to break the quill, magically transforming everything it has written in the last minute to almost perfectly match the original handwriting of whoever you were copying last. Creatures have disadvantage on checks made to realize it is a forgery.