The twelfth tiny thing is a Tiny Earth.
He spends most of his time trying to get the tiny continents to quit talking all at once.
Antarctica (bottom right) is the only one who ever listens, of course.
Thank you all for the great suggestions for tiny things! Your ideas are super helpful and inspirational, so please keep them coming in the comments. If I end up making the tiny thing that you suggest, you’ll get a free (not-tiny) pattern!