Here are 7 types of unreliable narrators: http://the-writers-society.tumblr.com/post/124074055929/7-unreliable-narrators-to-twist-your-next-plot (linked to in the external link) (or google: "7 Unreliable Narrators to Twist Your Next Plot")

It's a fantastic article with an exercise at the end to practice creating your unreliable narrator! If you're reading SuperHero, Elena is an unreliable narrator. Can you figure out which type? ;)