Board Thread:General Discussion/@comment-24674051-20150505212116/@comment-24674051-20150507173010

Honestly, if you were going to do Once Upon a Time in Atlantica (or whatever you want to call the sea kingdom), you would need both Ursula and Ariel, in addition ot Posiedon, and possibly Eric, if you wanted it to stand any chance of success. And honestly, that would be the most difficult crossover imaginable, due to trying to do realistic CGI to handle underwater action.

And if you were going to used LM characters in a different cross over, then you could use Marina, with flashbacks that revolve around HCA LM. But that would be one episode, and used to establish Marina as a character. And even then, I would still tie in the already established LM characters at some level. Even Wonderland used already established characters (Robin Hood, Cora) and settings (Storybrooke) to help tie it into the OUaT universe.

I like the idea of Marina and incorporating the original HCA fairy tale, I just don't see that being an entire arc. (The character could be, with a more compelling plot line).