Stories change over time, and characters get added or subtracted every time a story is retold. And sometimes, an existing universe gains a new character who adds something special. Or not so special. Who's the best (or worst) brand new addition to an existing group of characters?
Please include a picture, poster, clip, book cover, comics panel or other image to signify the newly added character who made everything better (or worse.) And please mention his/her name, why they're awesome, and where they appeared. Thanks! (Thanks to Michael Weyer for inspiring this one.)
Top image: Felicity Smoak was an existing DC Comics character, but she wasn't a key part of Oliver Queen's supporting cast until she was introduced in Arrow. And she's become the show's MVP in so, so many ways. Meanwhile, pretty much the only character on Gotham who isn't an existing Batman hero or villain is Fish Mooney, who's also one of the show's weakest links at this point.