Your party has just entered a fearsome dungeon looking to complete their quest. Your Dungeon Master is scheming behind his Hexers Game Screen. You hear him chuckle. He takes out the warrior artwork, turns it around and inserts it with the back side facing forward. The warrior shield is now surrounded by weapons. Your party knows what this means. A new Act has begun. The warrior in your party is pleased.
A couple of hours later all players are engaged in an epic boss battle. One of the characters is petrified. What does that entail. Your quickly has the answer DM by reading his cheat sheet. The battle continues at a high pace. After a long battle, the boss is defeated. The Act of the Warrior is completed.
After the game the DM folds the screen, puts it in the nice box it came with and goes back home to prepare the next Act of his adventure.