I like the flash back episode, and it is perfect timing from a animator's point of view. It builds tension and it is a reminder of what led up to that situation. Whether it is properly done is whats makes or breaks the episode. In this case it was extremely well done. Also the snake the norland killed was on the ground and not in the sky, if that makes any sense, remember blue sea dwellers have a hard time dealing with white sea dwellers porblems. Also i agree that this animal was special, it is 400 years old and i also think it was bigger and stronger.