Twilight unrolled the scroll and read it aloud while Nyx and Spike both leaned in.
Dear Twilight Sparkle,
I regret to tell you that shortly before your message arrived, the royal palace came under assault from a squadron of flying turrets. Unlike GLaDOS's previous attack on Equestria, these turrets were not equipped with portal devices for capture. Instead, these were outfitted with the deadly weapons of those that you faced in her 'testing' chambers.
Thankfully, there were no fatalities as a result of this attack, but over a dozen of my finest Guards were severely wounded. I myself was injured by their weapons, but only superficially. I fear that the brutality of this assault means that GLaDOS's insanity is no longer tempered by her curiosity about our world, and that she now seeks nothing more or less than violent revenge against those who defeated her in the past.
Luna and I have gathered the remainder of the Guard, and will be arriving in Ponyville shortly to plan a counter-offensive. If GLaDOS has rebuilt the facilities needed to manufacture these machines, then it is almost certainly near you. In the meantime, it is probably best if you gather the other bearers of the Elements of Harmony, along with any other pony possessing the necessary skills to fight this threat. The rest of Ponyville's citizenry should be warned so that they might prepare to defend themselves if the worst should come to pass, and GLaDOS launches another wave of machines against the town.
Stay vigilant, and stay safe, my student. We will arrive soon.
Your loving teacher,
Princess Celestia
The ponies and dragon all gasped at the realization that the princesses had been attacked. They were grateful to hear that it hadn't gone nearly as badly as it could have, but the threat of what the insane machine might do next hung over all their heads. At the end of the letter, Spike asked, "So what do we do, Twilight?"
"Exactly what princess Celestia told us to," the unicorn replied. "Spike, you and I will gather the others. Nyx, I need you to warn everypony you can find about this!"
Nyx nodded in agreement. "I'm on it!" She closed her eyes, magic gathering in her horn as she focused on a spell, the alicorn soon splitting into two, then those two split into four. That was pretty much her limit, but while each copy would have almost no magic ability left over, she could still fly and cover four times as much ground this way. One by one, the Nyxes dashed out the door and took wing. The last one to leave, though, looked over her shoulder and smiled resolutely to Twilight and Spike before launching herself into the air.
Once they took flight, each Nyx turned toward a different corner of Ponyville, calling out warnings to the ponies below. Most were confused at first, not sure how seriously they should take the alicorn. When they heard GLaDOS's name, however, most remembered it well enough to immediately start galloping toward their homes and loved ones, locking themselves away and barricading the doors and windows of the buildings!
After just a few minutes of this, one of the Nyxes spotted something flying through the sky toward her. It was off in the distance and indistinct, but as she squinted, she was soon able to make out...