***
"There is a creature in our midst, majesty." One of the copper-clad guards said, his eyes narrowed and flashing dangerously. "Some kind of witch who wears your body and speaks in strange tongues."
Celestia's breath caught in her throat. "Have you informed Luna of this?"
"Not yet, m'lady. The beast requests to speak with you personally. It masks its own flank-brand with one mocking our sacred weapons. Should we grant it audience?"
"Has it threatened you, or any of our peoples?"
"...No. But its behaviour is unnatural. It takes your shape, but if it is a goddess, it is a goddess of black arts."
"Discord's magic has displaced many creatures, and most of them are friendly. I will let it speak with us."
"Very well, majesty."
The guards parted the flaps to the tent, and in stepped a creature that matched the captain's description almost perfectly. Sure enough, emblazoned upon its back legs were symbols of magic and witchery.
"Good afternoon." The creature said, its face curving into a smile. "It's good to see you, Tia."
Celestia bristled, looking at the creature with indignance. "You address your goddess so formally? There are those within the pony nation who call you a demon, or an ally of Discord. Speak carefully, and within your right."
"Oh, you must be mad about these, I guess. Sorry." The creature giggled, and with a flick of her horn the wings disappeared. This was met with gasps from all parties, and the thrusting of spears in the direction of the creature.
"Why are you here?" Said Celestia, her tone strained with anger.
"Call it a birthday present." The creature replied with a cryptic smile.
The captain of the guard stepped between the mage and his ruler. "Her majesty has no origin! She has always been! You speak blasphemy!"
The creature only chuckled at this. "I think her majesty has a lot more to her than you give her credit for. So, will she accept my gift, or no?"
Celestia stared down the creature for a long time, but rather than wilt under her gaze or turn hateful in its glare, the pony looking back at her smiled an earnest, tender smile. The battle-hardened regent was rewarded for her efforts with.
"You look so cute when you're doing that." One of the guards struck out at the creature at this, and found himself encased in a purple magic as a result. The creature sighed, approaching a flustered Celestia and her guards, whose attempts at protecting their majesty with primitive weapons were casually flicked aside. A now shivering, glaring Celestia stood from her throne.
"It seems I must have overstayed my welcome." The creature produced a smooth, silky sheet of parchment in a flash of more purple light. "I came here to say that even though it seems hard now, the country you'll build will produce amazing mares and stallions. Every step you take will bring you closer toward a wide, and happy, family. Keep fighting, Princess Celestia, even when it seems like it's impossible to win."
Celestia looked down at the parchment to find an older, rainbow-maned version of herself smiling back at her, surrounded by Luna and seven other mares she could not identify. Draped under her wing was the creature standing in front of her at the moment.
"Oh, and one other thing." The creature said with a wink. In a flash, Celestia felt the creature close the gap and bring their muzzles together. Her eyes slammed open at the contact, and as the lips drifted away she touched a hoof to her own. "I love you."
Celestia sat, dumbstruck, as the star-flanked enchantress alicorn strutted away, and the flash of a powerful teleportation spell resounded throughout the tent she resided in.
"What do you make of it, m...majesty." The captain of the guard said, standing shakily upon his hooves.
Celestia scratched her chin, looking down at the strange parchment with a curious smile. "I believe I like the term "Princess" better than "Goddess"..."