About Medium Mode
Two 6-picture boards and 8 seconds — the standard spot-the-difference challenge.
Good for: kids, families, classrooms, casual training.
About the Wizard of Oz Theme
L. Frank Baum's 1900 book is fully in the public domain. Follow the yellow brick road through a deck of scarecrows, emerald palaces, tornadoes and friendly lions — drawn from the original novel, not any later film adaptation.