5. Tamara 
Tamara is like Dr. Whale: theyve both been in more episodes than expected, but have had absolutely nothing happen to them. Compare Tamara to Greg, her partner in crime: while both have had a flashback episode, Gregs was used to explain his motivation and just why exactly he hates magic and Regina. In comparison, Tamaras flashback told us absolutely nothing about her. What could have been a backstory was revealed to be all a big lie at the last minute. As such, she's a bag of unanswered questions (how did she know Neal was from Fairy Tale World? where did she get her taser? why does she hate magic?) Which wouldn't be so bad, but Tamara has little to no personality to go with the questions. Tamara barely has any character traits beyond generic evil-at least Greg has dumb as a bag of rocks and "obsessed with his father" as well as generic evil. Considering that she ended up becoming one of the series finale villains, its disappointing how little we saw of her personality.