This is the bundle you will get all keys to all of the spin-offs:

Art of Murder - Cards of Destiny
Art of Murder - Deadly Secrets
Art of Murder - Hunt for the Puppeteer
Art of Murder - The Secret Files

All month of November is going to exclusively for my group: https://steamcommunity.com/groups/contests

So if you want to win join my group so you can see/view my future giveaways.