How can I create a function that generates a random value from a table based on a true/false value that each value has? (In Google Sheets.)

I'm creating a checklist for my Terraria collection and I have each item in multiple tables across multiple sheets. In Column A there are the items listed in various tables, and in Column B is a True/False value based on whether or not I have the item. I would like to add a feature that generates a random item that I haven't collected yet. I would like to be able to have the function work across all the sheets in the file as well in the individual sheets.

I'm using Google Sheets and here's the link to the file so you can see how it's formatted: http://ift.tt/1Pufvb3