A Brief Digression on the Sea Ponies · 8:56pm Feb 10th, 2015
I go with the idea that there's a race, the Sea Ponies ...
... who were ancient allies of the other Three Kinds, ...
Shoop-bee-doo. Shoop-shoop-bee-doo.
Call upon the Sea Ponies, when you're in distress.
Helpful as can be ponies. Simply signal S-O-S.
If you find you're past the drift and haven't got an oar (oar).
Count upon the Sea Ponies, they'll see you to shore.
Shoop-bee-doo. Shoop-shoop-bee-doo.
... practicing acoustic magic which gave them mastery over water and its interface with air.
They became estranged during the Dark Age and downright terrified of land-dwellers because of the Cataclysm.
Their lives and magic have always centered around acoustics and song ... they navigate with active sonar, communicate by sending each other image-pictures via sound, and cast spells via song. Their elite magic-users are called "sirens," and some of them ...
can be powerful, even
terrifyingly powerful.
Many of the Sea Ponies have by modern times merged with a pre-equine aquatic race, the Deep Ones ...
... producing the Deep Ponies ...
... who maintain shore colonies, dwelling (for the most part) peacefully beside the other Pony Kinds, trading and occasionally interbreeding with them.
Neither the Sea Ponies nor any of the their variant races are inherently evil. But their cultures have become very alien since they became shy of the land-dwellers over 5000 years ago, and misunderstandings are possible and can be mutually-lethal. They have a strange philosophy in which "safety" and "treachery" are similar concepts, in that one is "safe" when one understands the dangers surrounding oneself, and hence one must always be alert for the ways in which one's behavior can create "treachery" from the environment. They are honorable, but sometimes only to their literal words, and they have very little forgiveness for foolishness or appreciation for excessive and irrational trust.
For instance, if one insisted that an amulet purchased from a Deep Pony gave one the ability to breathe underwater, and ignored her attempt to tell you otherwise, she might not feel too bad about someday encountering your remains some weeks down the road, while a Land Pony would probably be seriously upset by the discovery. And if you met and courted one, not knowing what she truly was, I'd be think twice about backing off one's Intention after coming over to meet her family and discovering that they were a bit more ... unusual ... than one expected.
Speaking in a purely theoretical sense -- not that either of these two events might happen to any particular Deep Ponies. 
And, of course, some Sea Ponies are evil, like the Dazzlings. Or just very, very focused on a goal and unconcerned about the lives of any in her way, like Cassie the Kelpie. Or not evil, but arrogant and hard to get along with, like many of the aristocracy of Kelplantis. Or just plain strange, as are many of the Deep Ponies, including no one in particular.
The Reconciliation also proceeded between Equestria and the disparate races of Sea Ponies, but they were neither as pathetic nor in need ot Equestrian help as were the Changelings, and while this Reconciliation was in some ways easier, it was fraught with diplomatic difficulties of its own.
I like to think the sea ponies are simply beleaguered. Assuming that Equestria's planet is similar to Earth, then there's twice as much area underwater as above it, and that means twice as many potential Everfrees, Badlands, and other hot spots of incredible danger. More, actually, given that beneath the waves, volume becomes a more important consideration. Alien krakens, proud serpents, ancient leviathans... and then there are the unthinking or barely thinking menaces like sharks, dolphins (imagine an entire species of Mirror Pool Pinkie clones,) and giant crustaceans. Krakens may not think like ponies, but they can be reasoned with to some extent. Trying to negotiate with the rainbow death will end in tragedy and a well-fed giant mantis shrimp.
That said, I do love your Lovecraftian take on the subject, especially the involvement of nopony-in-particular.
Yes. There are a lot of dangers in science-fantasy seas. At least to the Deep Ponies the Deep Ones are allies rather than enemies, or their lives would be even more dangerous. Most of the other Sea Pony races have at least treaties of mutual non-hostility with the Deep Ones, who are actually pretty honorable according to the original Mythos stories ... cold and sometimes cruel, but they do keep their words, an important trait for a race of immortals.
Ipsy Witch, who is of course the subject of those pictures and the source of the specific examples, is actually a pretty nice Deep Pony. She's a good example of how the cultural differences can cause problems even for Deep Ponies who are trying not to cause trouble with the land-dwellers.
By the way, in their very first apperance, the whole point of the song the Sea Ponies were singing to Megan and Applejack was a reminder of the pact which existed between Dream Castle and the Sea Ponies, one which predated the Time of Extermination itself. In other words, they were saying "Between us is alliance, not treachery, and we consider ourselves bound to help you at your severe need." Which is something they might not have bothered to say if they had not been very aware of the possible alternatives.
Got a broken image, right above the Deep One.
Also, the bit about their concepts of "safety & treachery" puts me in mind of Marathon Man. I can just see an early diplomatic encounter being a sea-pony asking the land-pony "Is it safe?" over and over again.
2785789
Wait, so who can you see? Cassie the Kelpie? The Deep One? Ipsywitch?
2785798
What I see is:
Unless you mean "who do I see in the Is it safe?" scene, in which case I vote for the Dusty Hoofman and Laurence Oystier.
2785842
Reloaded the link to the Cassie the Kelpie image ... can you see it now ...?
(I bet Alex Warlorn, who hates that character's guts, is laughing at this obvious curse ...
2786012
Hm, no. If I try to open it in a new tab and add a www to it though, it works then.
2786043
By the way, the reason I love that first picture of Ipsy Witch is that it makes a point, something also true of the humanoid Deep Ones. In the water, their natural element, they are lovely. Something Lovecraft could not totally grasp,between his thalassophobia and his xenophobia. But he must have understood it on some level, or he never would have created them.
This reminds me of the setup in "MLP Time Loops", in which the Seaponies are insane pyromaniacs because of their role in fending off the abominations that always seem to inhabit the deep sea.
2786056
Well, that's a key part of true horror, isn't it? That fascination with it, the inability to look away or think of anything else. The attention to detail and how it's described so evocatively... someone attracted to a thing and someone repelled by it will both paint a much more vivid picture than someone in the middle.
In the Pony POV Verse, it's part of the canon that Rarity and Sweetie Belle have seapony ancestors on their father's side, and this is WHY their hooves can get pruney in water.
Under the Sparkling Sea I think shows in a rather positive light that things have finally moved along between the land and aquatic ponies.
2786436
(*nods*)
... and I implied a link between Melody and the Pies through Harmonia's grandmother with the creation of her mother, Sweet Melody Pie. Who, since they're Harmonia's and thus Proserpina's ancestors, are also ancestors of Octavia.
2786135
Well, this is a world of history layered in lost civilizations, extinct or simply-forgotten races, and strange magics. Why wouldn't the seas be like something out of H.P. Lovecraft? Love the sea, fear the deeps, it's all the same thing to the Sea Ponies. It's a very harsh and cruel environment, and while they can be very friendly, they can be harsh and cruel as well -- depending on whether they see you as friend, foe or neutral. They aren't as dominant over their environment as are the main Three Kinds over theirs.
2786910
Like you said, so few ponies survived the multiple disasters that tried to wipe them out, that everypony is gonna be related to everypony those who survived.
2786149 A friend of mine has this sort of coincident horror and fascination in animatronics. For her, Five Nights at Freddy's is a match made in Hell. Incidentally, she's a longtime MLP G1 fan, but not a G4 fan(and "We do not talk about Tales").
2786436 In the Pony POV Verse, it's part of the canon that Rarity and Sweetie Belle have seapony ancestors on their father's side, and this is WHY their hooves can get pruney in water.
And now I'm imagining Rarity and Sweetie going through their very own Innsmouth Horror as they both visit some very, very distant relatives and get a nice big hug from Aunt Blibdoolpoolp.
EDIT: For that matter, with all the Pony/Lovecraftian crossovers, I wonder if this means that the Diamond Dogs are descended from H.P.L.'s ghouls? Both canine-like humanoids, both live underground, both have hostile if wary relations with the surface-dwellers...
2792002
Hmm ... that might actually make sense! All of it ...
"I also met that which had been her grandmother. Darling, she simply had no sense of style, none of them did, but I came to a pleasant arrangement with That Which ruled the city, and Rarity Enterprises is opening a new boutique in their shore colony ..."
(The Hinnysmouth Makeover, by Rarity Belle)
...
including perhaps the speculations about the Diamond Dogs.
2792002
King Leo, "Do I look like Ponythulu to you?"
2792102 Hmm ... that might actually make sense! All of it ...
"I also met that which had been her grandmother. Darling, she simply had no sense of style, none of them did, but I came to a pleasant arrangement with That Which ruled the city, and Rarity Enterprises is opening a new boutique in their shore colony ..."
(The Hinnysmouth Makeover, by Rarity Belle)
I can actually see Rarity doing this with the Deep Ones, too. Poor old Y'ha-Nthlei will never be the same.
2792194
King Leo, "Do I look like Ponythulu to you?"
Is this a trick question?
2794265
I just mean Under The Sparkling Sea.
2794440
I just mean Under The Sparkling Sea.
I guess I'll have to look at that one of these days.
I actually covered this interesting topic once.
there are Sea Ponies (either Hippocamps, Piscene, Octoponies, or Ronesequi), which are descended from earth ponies, and Sirens and Morgen (like Cassie the "Kelpie"), which are actually closer to changelings.
For those that still have all four legs, there's
Deep Ones (like Ipsy)
Cappal Uisce (aka Shark Ponies)
Kelpies
Nixies (actually unusual in that they have separate toes and are genetically closer to Eohippus than actual ponies)