Learning Atlantean is Possible...and Very Hard!
Recently I rewatched the Disney movie Atlantis: The Lost Empire, and after looking it up alittle bit afterwards I found out that someone went out of their way to construct an entire language for the movie, all with its own vocabulary, phonetics and grammar! Here's a look at the alphabet/numbering system:
Other cool things to know about Atlantean:
Remember that someone I mentioned who constructed this language? It was none other than Marc Okrand, the man who invented the Klingon language for Star Trek!
Here's a clip of Okrand teaching Atlantean: https://www.youtube.com/watch?v=shWTxkCdn80
Atlantean was divided into two uses: the first being as a simple cypher code (as the video above and the image I posted use) and the second being a full-fledged constructed language. The key difference is that Atlantean Code has 29 letters while Atlantean only has 20. The letters c, f, j, q, v, x, z, ch, and th were later added to market the language as more of an easy cipher code (presumably to make it easy for children who watched the movie to learn?), but weren't used to formulate any of the words in the Atlantean dictionary: http://www.freewebs.com/keran_shadlag/eadictionary9710.htm.
In the movie's mythos, Atlantean is meant to be our world's "Tower of Babel" or the root of every language on the planet; nine thousand years ago Atlantis was a civilization that spawned an empire over much of the world, whose capital succumbed to a great cataclysm and remained isolated from the world - under the ocean - for over hundreds of thousands of years. Based on this fact, Okrand combined Proto-Indo-European (the ancestor to Romance, Germanic, Slavic, and Celtic languages) with ancient Chinese and Biblical Hebrew to construct the vocab, and formulated the grammar based off Sumerian and Native American languages.
Atlantean reads in the very ancient and quirky Boustrophedon format, meaning you read lines of text alternately between left-to-right and right-to-left in a zigzag, or snake motion. This is supposed to represent the flow of water. (Side note: Very Ancient Greek was written in this format, and very recently the Raga language of Vanuatu has adopted it.)
Maybe someday Duolingo may take a stab at this language?? They've already been thinking about adding other fictional languages (Kilngon, Dothraki, and Sindarin are listed on the Incubator page, along with their own symbols already designed)!
For language geeks, the Wikipedia article has an exhaustive rundown of phonetics, word order, grammatical cases and more: http://en.wikipedia.org/wiki/Atlantean_language