Austraeoh is a lengthy ongoing My Little Pony: Friendship Is Magic fanfiction series by Imploding Colon. New chapters have been released daily since May 2012. There are currently five stories: Austraeoh, Eljunbyro, Innavedr, Odrsjot (200 chapters each), and Urohringr (ongoing).The official story summary is the laconic "Rainbow Dash flies east." Indeed, that's the only thing that happens for a while as the story begins: Rainbow Dash is flying in solitude across uninhabited scenic landscapes, and is about to reach the eastern edge of a map of lands known to the kingdom of Equestria. Where is she heading? Why has she left home? Why does she keep the Element of Loyalty on her? Any answers to these questions will not come early in the story.The author, Imploding Colon, is an alias of shortskirtsandexplosions, author of well-known fanfics Background Pony and The End Of Ponies, a fact that was not known initially and came as a surprise to many readers. The author has spoken almost nothing about Austraeoh, only briefly acknowledging writing it in some recent blog posts. Although the author never replies to reader comments, he seems to enjoy reading them, as hidden references to last chapter's comments occasionally appear in the next chapter. Starting from about the mid-point of Austraeoh (the first story in the series), most characters and places have been named after frequent commenters on Fimfiction.Net.
Aerith and Bob: partially caused by the author's practice of naming characters after commenters' nicknames. Aeriths include Zaap Nator, Floydien, Khao, Zaid, Zytharros, Arcshod, Lasairfion. Examples of Bobs are Sam, Stu, Dalton, Jasper Clark ("It's a northern name") and Simon. Then there are traditional (canon-like) pony names such as Gold Petals, Whitemane and Nightshade.
All Just a Dream: a number of chapters in Innavedr. Nightshade captures Bellesmith and plugs her into a sequencing machine to trick information out of here. As the chapters are through Belle's point of view; the reader doesn't learn it until several chapters later. As those chapters were released, some observant readers guessed it already at the first or second dream chapter, due to Kera behaving "out of character".
Authority Equals Asskicking: In addition to Prince Sam Rose from Silvadel, we have Prime Enforcer Shell. He's pretty much the leader of the enforcers, and is just as Badass as Rainbow Dash.
Badass: Rainbow Dash, so much. Also Steelteeth, Roarke, and definitely Prime Enforcer Shell.
BFS: The Xonan general Zytharros has a magical sword "twice the size of any full grown pony".
Big Bad: Prime Enforcer Shell is this for the majority of Eljunbyro, Innavedr and Odrsjot. After him, the next big bad seems to be none other than Queen Chrysalis.
Big Good: Queen Whitemane, in the first two books.
Bilingual Bonus: the titles are composed of Old Norse words. The meanings of Eljunbyro ("endurance (re)born") and Odrsjot ("frantic compansionship") are mentioned in the text. The others can be translated as "east horse" (Austraeoh) and "accomplish-wind" (Innavedr).
Diabolus ex Machina: In Odrsjot. Belle, Pilate, and Kera have been left in Lerris, where they can start a new life away from war ... and then Shell shows up and slaughters the entire village. The three of them survive, but not without scars.
Doomed Hometown: And how. Kera has this really bad. No sooner than she arrives at the place she decides to settle down in with Bellesmith and Pilate, which was her hometown before abducted by Nightshade, Prime Enforcer Shell shows up and spreads the fun to everypony!
Door Stopper: As of 2014/01/01, this story is seven hundred and twenty-seven chapters long. And it's still not complete.
Downer Ending: played with, but subverted. Austraeoh seemingly ends with Rainbow dying, but she gets better in Eljunbyro (although it isn't clear that she survived till halfway in Eljunbyro). In the end of Eljunbyro, several main characters get thrown off an airship, but the very ending reveals that they all (unbeknownst to each other) survived the fall.
Disney Villain Death: Enforcer Shell gets bucked off a bridge by Rainbow Dash in chapter 95 of Eljunbyro. He survives.
Dream Within a Dream: Bellesmith experiences a severe confusion of dreams and reality when Madame Nightshade plugs her into sequencing while she sleeps and makes her believe that the events of Eljunbyro and Innavedr were hallucinations experienced under sequencing in Blue Shelf. Belle is first driven to suicide in the dreamworld and then made to experience a false awakening in Blue Shelf.
Driving Question: Why is Rainbow Dash flying east? At least for the first half of the first story.
Eldritch Abomination: the chaos monsters in Windthrow. Also, what Rainbow becomes when her pendant is removed. And Nevlamas.
Flash Back: several such chapters occur throughout Austraeoh, slowly unveiling the backstory. Then in the first half of Eljunbyro, we finally get the entire backstory in form of several multi-chapter flashbacks.
Imposter Forgot One Detail: Played with. The changeling impersonating Prowse did know he has an accent ... but it failed to realize that he only uses that accent as a marketing gimmick. Unfortunately, Prowse's niece Props has forgotten this since she last saw him.
More generally, changelings have green blood, even when transformed.
One Steve Limit: broken with the name Zetta, borne by two characters (one a stallion, the other a mare). Also, Bellesmith is usually called Belle, which generally stands for Sweetie Belle in this fandom.
One-Winged Angel: Lady Pestiferous can turn into a mechanical pony-spider hybrid at will.
Our Dragons Are Different: The dragons that appear in Austraeoh are, to make a massive understatement, not as friendly as Spike. The dragon Matriarchs are apparently ancient creatures older than the alicorns.
Pensieve Flashback: through a technology called "sequencing" in the country of Ledomare. Can only be done by unicorns whose horns have been lost or removed. Curiously, this can be done even if only a skeleton is left of the subject whose memories are accessed.
Samus Is a Girl: Roarke is female. ...Not that you can tell from all the armor she wears.
Sanity Slippage: Shell seems to be getting more and more insane with every appearance. Bellesmith too, but to a lesser extent.
Significant Anagram: this doesn't come up in the story itself (and probably is just a coincidence in-universe), but Noble Jury, the name of Floydien's airship, is an anagram of Eljunbyro. The author named the ship after a chatroom of the story's fans, whose name in turn was created by putting Eljunbyro into an anagram generator.
Survivor Guilt: Rainbow has this big time, especially evident in Eljunbyro. She actually has a reason to blame herself too, having succumbed to Discord's temptation.
Shattered World: Equestrians generally know that the world is a plane, much longer in the east-west direction than in the north-south. In Innavedr we learn that this is only a part of the formerly ring-shaped world, long ago shattered into pieces.
Stealth Pun: a mysterious group of merchants, which for some reason is called "The Lounge", is mentioned in Odrsjot. In Urohringr, we learn that they are anthropomorphic lizards.
Steam Punk: many of the civilisations east of Equestria run on steam power combined with magic.
Sweet Polly Oliver: Gold Petals, who has to pretend to be a stallion to get to join trade caravans.
Title Drop: In Austraeoh, this happens in the last chapter. Even then, the meaning of the word "Austraeoh" is not explained at all till Eljunbyro. In Eljunbyro, Innavedr, and Odrsjot, the title drop happens earlier. In all three cases, it's in the form of a character suddenly and unexpectedly uttering the title word.
Villainous Breakdown: Prime Enforcer Shell gets one in chapter 174 of Eljunbyro. And it only gets worse from there...
Well-Intentioned Extremist: Madame Nightshade, whose goal in life is to end the war where he lost his brother. To do this, among other things, she kidnaps unicorn foals and cuts off their horns (It Makes Sense in Context). Although much less sympathetic, Duke Zaap Nator might also count, sacrificing innocent foals in order to save his city of Darkstine.
Khao and the cultists count too. They genuinely belive they are Eljunbyro and want to help Austraeoh achieve her destiny. It just so happens that they kidnap and attack the real Eljunbyro in the proccess.
What If?: When Rainbow Dash abandoned her friends under Discord's influence and the others tried to use the Elements of Harmony against him without her, instead of just not working, the Elements kill them.