Things we don't like about the show

ATLA is an amazing show, one of my favorites, but I have one pretty big complaint. I feel like the giant lion turtle was in some ways a cheap way out, the problem it addresses (the fact that Aang will have to kill Ozai to stop him) was a big issue for Aang morally, but with the power the giant lion turtle gives him it feels unsatisfying. It completely solves the problem with no loose ends, and that'd be fine, if it didn't come out of nowhere. There was no foreshadowing besides a quick mention of them in the library episode, and even then it has no mention of their power, only an image and Aang saying "Hey, look at these weird lion turtle things.".