Guard Stan:
Ah, the Silver Dryad. I will give you one Silver Dryad for 5 silver fairies and 5 Silver Golems. Or perhaps you would prefer a game of chance?
Accept standard exchange rate
Play game. [Guess correctly in two tries - 3 silver fairies]
Play game. [Guess correctly in three tries - 7 silver fairies]
Play game. [Guess correctly in four tries - 9 silver fairies]
Explanation of game