Spearsight looked up when he felt something knock his helmet off. The helmet clattered on the stone path beneath his hooves. A lone falcon was retreating into the sky. The pony bent down to replace his helmet.
The falcon landed at the top of a pole bearing Crystal Empire's flag. The great bird, silhouetted by the full moon, opened its beak and let out a powerful cry. A shiver ran down Spearsight's spine. The defensive Crystal Wall along the empire's northern border was eight ponies high, and at night the winds up here could chill a pony to the bone. Spearsight regretted not dressing more warmly for tonight's patrol.
Spearsight spun around when he heard another clattering sound against the path. A few paces away he could make out a grappling hook that had landed on the path. Somepony was trying to scale the wall. A smuggler perhaps? He trotted over to investigate. He leaned over the wall, peering into the blackness below, his eyes straining to discover where the rope led.
With a whooshing sound, he saw half a dozen more hooks coming straight at him. He looked up and down the path. There were dozens more grappling hooks landing now. Spearsight broke into a gallop, heading towards the nearest tower.
"We're under attack!" he shouted to anyone who was listening, "light the signal!"
As Spearsight neared the tower, two enormous hulking monsters blocked his path. He skidded to a stop. Minotaurs: creatures with the head of the bull and the body of, well, something not of this world. The two monsters smiled at the earth pony and slowly walked towards him. Spearsight knew that the fate of the empire could be within his hands. History would judge him for his actions tonight. He charged straight at the largest minotaur. The bull-headed creature braced himself for an impact that never came. Spearsight threw his legs forward and dived between the monster's two legs, skidding along the path and emerging behind them. He broke into a gallop towards the tower door.
Spearsight barged through the door and bolted up the stairs to the top of the tower. At the top, there was a huge cauldron full of a flammable liquid — the signal fire. He went for the small flaming torch, kept here for precisely this purpose, grasping its handle in his teeth.
As he approached the cauldron, a dark figure leaped onto the tower wall opposite him and leaned on the flag pole. Another minotaur — he must have been at least twice the size of even the larger one downstairs. The falcon flew down and perched on the great beast's shoulder. The pony and the minotaur locked eyes on each other.
Spearsight spat the torch into the open cauldron and the signal fire instantly erupted in flame. Seconds later, he saw the signal in the next tower burst into flame too. And moments later the next one.
Spearsight narrowed his eyes at the minotaur and addressed him sternly, "Now all of Equestria knows you're here."
The minotaur pulled at the flag pole, snapping it like a twig. He lowered the flag into the signal fire, watching the flames lick at it. The monster looked up and smiled at the pony before opening his mouth to speak. "Perfect".