Scales adds two weighing puzzles to a GameMaker game. In the first, a hoard of 3 to 13 coins hides one false coin and the player finds it in the weighings allowed. In the second, they weigh out an exact amount of goods with a box of weights.
The false coin isn't picked in advance. Each weighing falls the worst way for the player, so a lucky guess never wins, and every puzzle allows exactly the fewest weighings that always suffice. A hint function gives a weighing that keeps the puzzle winnable.
Everything is drawn in GML with no image files: the counter, the balance with a swinging beam, 90 coin designs, the weights and the goods.
The code was written with AI. It's $11.99.