When you find Black Widow, be sure to get a number from her so that you can find the Avengers Secret Base, which is a Bonus Cache in this series.
This series requires stealth, like that of a super hero to ensure that it isn't muggled. Please use caution to keep these around. I know they aren't the best type of hide, but I am hoping that they will be enjoyed based on what they are about and their swag.
The cache is starting off with several Black Widow stones. Anyone in the FTF party may take one without trading if they so choose.
Thank you for finding my cache!