How does Pushkin illustrate the theme of obsession in "The Queen of Spades?"

Pushkin focuses Hermann's obsessive nature from the start. Hermann never gambles, but he watches and observes, as if he is playing himself. When he discovers that the Countess knows the secret to winning, he becomes obsessed with finding out what that secret is, slowly ingratiating himself with Liza. When news arrives that the Countess is dead, Hermann After the Countess's death, Hermann is consumed with the idea that the Countess' spirit will bring him bad luck. In the end, obsession devours his mind, leaving him completely without rational thought.