Short version/vital info: The Vale is set in an alternate-universe Equestria and features a few major breaks from canon, including:
-Celestia and Luna are the only princesses (this is strictly due to cutting down on canon characters.)
-The Crystal Empire was never lost to the world, though its remote location means it's fairly self-contained. They do have a reigning Emperor/Empress, but ultimately do fall under Celestia's rule, should she ever give some kind of specific decree.
-Discord was never released.
-The Mane 6 are around, but more in a 'background pony' capacity-- no Elements of Harmony, and if for some reason they ever do come into play in this setting, they will probably be given to OCs because hey we're already in this deep. That said, I would prefer they just not come up at all.
-Most species are allowed for OCs in this setting, but there will be no starting alicorns. At all. Though Cadence and Twilight haven't earned their horn/wings here, we are following the rule of 'Princess/alicornhood is a title you earn through incredibly hard work and unique magic', and... well, I'm not totally discounting the idea of it happening at some point if this goes on for a while, but it's not likely. However, I will happily accept: Bat ponies (pegasus only), Crystal ponies (mostly earth ponies, but pegasi and unicorns will be accepted), donkeys, griffins, zebras (as this is diverging from canon, I will allow unicorn or pegasus zebras)... and since they're so popular on CS, deer (however, I'm going to have to draw the line at deer/pony hybrids in this place xD). Diamond Dogs, Changelings, whatever Sombra is, Draconequi... pretty much anything not listed above will not be allowed.
-This setting also has a unique unicorn offshoot, though they do not have any special name (yet). These unicorns are:
- Taller and slimmer than the average pony (somewhere between Fleur and the Saddle Arabian ponies... horses... whatever they qualify as.
- Have longer, clearly spiraled horns-- they sort of bulge out instead of having flat sides like usual MLP ponies. These horns can sometimes be a different (single, there won't be any spectrum horns or anything like that) color from their main body, usually the same color as their hooves.
- Have cloven hooves and long fetlocks, the latter of which are always the same color as their manes.
- Some (applies to males and females) of these ponies have little goatee-beards, but this is completely optional.
- Long, lion-like tails, with a long fluff of fur at the end.
-There are virtually none of these unicorns outside the Vale, though a rare few have left for various reasons over the centuries. More often, outsiders will wind up finding their way into the Vale, and be kind of... well, not allowed to leave. The unicorns of the Vale are are incredibly concerned with their privacy, and do not like to risk outsiders revealing where they are.
-These unicorns do get cutie marks.
-Aside from a rare outsider, there are no pegasi or earth ponies here. However, these unicorns have developed magic for weather control, and a few are even capable of 'flight'-- they can create little pats of ice from water vapor in the air, and run along them, though they must always work in pairs due to the high risk of injury in that job.
-The Vale is a large island, located in... I'm calling it a lake, the big blue area between the Crystal Empire and the Crystal mountains. The residents there have cultivated a thick forest that runs around the outer edge of the island, and is filled with dangerous beasts (more on them later). However, the rest of the land is mostly made up of grassland, some hilly areas and some flat places, and a few smaller forests/groves; as well as orchards and farmland. These ponies do not have real 'roads', the most you'll see are well-kept dirt paths, and houses are usually very modest and fairly undecorated. The only exception is the royal castle, which also serves as the overall social hub of the Vale.
-The Vale is ruled by a Queen, though she has more or less abdicated the throne and a descendant now rules in her stead.
-Despite their best efforts to keep the Vale a secret, it is heard of in the outside world... as the subject of a fairy tale, and any pony who proposes the idea that it actually does exist is usually dismissed as a crackpot.
-The ponies here, whether outsiders or born and raised there, tend to live half again or twice as long as average ponies, and have a curious resistance to most disease, and heal quickly from injury.
More detailed information will appear in the next few posts.