I was taking a closer look at the Prophecy, and thought it might be nice to have a hub for discussing it. The following is the full text from "XV."

One day, the south will erupt,
Bringing forth darkness from the seas,
A Lord of darkness and despair from parallel,
Encroaching on our own from distant part.

An Oracle will rise, given power,
The third eye, to see what is to come,
And what cannot be known,
For the truth is a horrid thing.

They will quest to the six altars,
Consulting the spirits within,
Gaining their wisdom and aid,
Purifying herself to be one.

They will use our remnants,
Distort the natural order,
Find the power overwhelming,
And banish the Lord of darkness.

So all must prepare for then,
Give them assistance with the time,
For the knowledge is all they need,
To organize the defeat of a cataclysm."

What's really bugging me is the second paragraph. An interpretation that all the characters seem to take as fact is that the Oracle will have a third eye that allows them to see the future, and to see "what cannot be known," whatever the hell that means. But then there's the last line of that paragraph, "For the truth is a horrid thing." This just doesn't seem to fit that interpretation.

An alternative, which I'm still toying around with, is that it actually refers to multiple individuals. I think there may be two disparate entities, which together are the Oracle.

An Oracle will rise, given power,

This could, if it's bad English, refer to an individual rising and being given power, but it makes more sense if the Oracle rises from the gift of power.

The third eye, to see what is to come

I'd say that this is Orchid, who sees the future.

And what cannot be known

This, I think, refers to Twilence. She is the only thing which we have seen Orchid unable to foresee. She is, quite simply, what Orchid cannot know. Additionally, we, through her Eye, provide her with knowledge which she should not be able to know.

This, as it turns out, allows for a sensible explanation of the fourth line,

For the truth is a horrid thing

By dividing the ability to see the future, and the ability to see beyond the world of the story, those who possess these abilities are protected from the potential consequences of literally seeing all of reality at once. Which would probably be bad.

Then there are the pronouns. The prophecy uses both plural and singular pronouns to refer to what seems to be the same thing. Assuming that this isn't just an artifact of being translated from another language poorly, this is incredibly significant. The Oracle is at once multiple individuals, and a singular female. I've been able to think of two possible interpretations of this, which are not necessarily mutually exclusive.

• One: It refers to the two parts of the Oracle, who achieve either metaphorical "one"ness (teamwork and friendship), or literally merge together to be one creature.
• Two: It refers to the Oracle, having achieved literal unity, and the various altar spirits.

I think you're focusing too heavily on the second paragraph and ignoring what could be vital information in the others. See, regardless of what 'seeing the future' may mean, the prophecy is in fact referring to Twilence due to the fourth paragraph.

They will use our remnants,
Distort the natural order,
Find the power overwhelming,
And banish the Lord of darkness.

The first two lines dictate that whoever it is, they're an outsider. They will use our remnants.

The second line confirms this. because no natural system can be disturbed from with-in, if there is harmony in an order, it will stay that will until disturbed by an outside force. Our outside force. Twilence came from outside this world, with we in tow. She went about immediately asking around, doing things differently and generally just being an alicorn, which in and of itself was entirely unheard of. And let's not forget the moving the sun incident.

The third line is, I believe, something that's either already happened in the form of Twilence freaking out at us and just her general personality shift from wholesome and naive, to what she is now. Or has yet to happen, in the form of us doing something that essentially breaks her (which will be an accomplishment at this point)

And the fourth line is irrelevant as it's a prediction of an event that has yet to happen.

Remember, Orchid may have the ability to see the future, but she is still native to this world, she's still a part of it. Meanwhile, Twilence, and everyone she summons from the alters is not

One day, the south will erupt,
Bringing forth darkness from the seas,
A Lord of darkness and despair from parallel,
Encroaching on our own from distant part.

while most of this seems self explanatory, the third line of this to me seems to indicate that the dark lord may be another like vriska drawn from another world, while the second paragraph does seem to talk about multiple people and it does lead into the next one refering to a "they" it becomes confusing when it soon after refers to her "purifying herself". for the most part it continues to refer to multiple though and im pretty sure we've already distorted the natural order by now to at least some extent.

The way the first and second stanzas flow together sounds like the dark lord has already come into existence. Food for thought.

One day, the south will erupt,
Bringing forth darkness from the seas,
A Lord of darkness and despair from parallel,
Encroaching on our own from distant part.

Those last two lines make sense now. Took me a while to realize this, but they must be talking about the fact that both Corot and siron both come from their own stories, and they're being used in The Influence.