I don’t want to give away anything about the ending. But I do want to say that it is amazing. I’m always disappointed in the purely child-directed stories within the epic war, so there were a couple of parts that I could have gone without, but overall, the ending is not disappointing. The pieces fall together smoothly with incredible fight scenes, perfect character development, and with the message of peace and freedom that the series has carried throughout.
If you haven’t already started watching Avatar, you need to. With the series completed, there’s no waiting for releases. I promise once you start, you may not be able to stop. And since it's summer, you can revisit those old Nickelodeon days of sitting lazily on the couch, and watching an animated series that will blow your mind.