Hermman has hallucinations of the supernatural events that occur in "The Queen of Spades". While he is playing the last game against Chekalinsky, Hermman "sees" the queen of spades wink at him thinking it's the old woman, which is only occurring in his mind because the people around him watching do not notice anything. Also,Hermann's desire to win while he is playing, is causing the supernatural forces because they did not occur ealier in the story since he had never played.
On my own thoughts, I think Hermann is a corrupt character because he hurts Lisaveta by making her believe that he loves her in order to get close to the countess which I think is very disturbing. He is a cold character because he does not care about Lisaveta's feelings and he doesn't really repent for I guess causing the countess a heart attack. It says, "Although unrepentant, he could not altogether silence the voice of conscience..." (299). Analyzing this quote, it shows that Hermann feels guilty but does not repent because he is cold hearted and attends the funeral in vain.