Upon commencing normal operations, the first thing the Brain of Fort Crow did was gather information.
It compiled data with clinical efficiency, beginning with the current era and date. By intercepting the conversations of the humans within the fort as well as those of the surrounding soldiers, it was able to grasp the broader situation.
As for the specific date, it had simply queried the automata accompanying the human who had reactivated it—Dajure Harvey.
Learning that the date was March 10, 3458, the Brain calculated that 303 years had passed since the Great Magic War ended in the year 3155.
<<Free ether concentration is low... This is likely a result of the Ether Stampede. It appears natural recovery is still incomplete, even after more than three centuries.>>
The Brain analyzed these realities, cataloging them as immutable facts. It then proceeded to identify the number of people within Fort Crow—which, in a functional sense, was its own body.
<<Eight people... No, nine.>>
Furthermore, it noted that six combat golems had been activated and that the magifortress assistant automata had been woken up. It also registered the presence of several active utility automata.
<<Hmm...>>
Up to that point, everything was within expected parameters.
However, for what purpose had the combat golems been activated? Naturally, it would be to engage a hostile entity.
And what was that hostile entity? By all logic, it should be the demon race.
What were the defining characteristics of the demon race? High mana density and superior physical capabilities.
<<And the current opposition?...What is the meaning of this?>>
Construction of Fort Crow had begun during the mid-stages of the Great Magic War, utilizing the pinnacle of magical engineering available at the time.
It reached completion as the war neared its end.
Given its geographical location, it was intended as the final line of defense. To its south, across a river, lay the capital of the Dinar Kingdom—the nation that served as the center of human unification during that era.
Fortunately, the fortress was never tested in actual combat.
Only three days after its completion, the Ether Stampede occurred, bringing the Great Magic War to an abrupt conclusion. Most of the Magi Machines within the fort were sealed away without ever being used.
Under normal circumstances, a period of several days to a few weeks would have been dedicated to operational checks—what one might call "debugging" in modern Earth terms—but this crucial step was never executed.
The governing Brain was no exception to this oversight.
Without anyone realizing that flaws existed within its logic, the fortress fell into a long slumber that lasted for over three hundred years.
<<Humans are fighting amongst themselves? How can such an absurdity be happening?>>
Although the Brain had woken up from its three-century sleep, its knowledge was significantly skewed. More accurately, it suffered from a profound lack of education.
<<Engaging fellow humans instead of the demon race... What is the rationale?>>
Normally, a commander with command authority would be stationed above the Brain to issue general directives, monitor its actions, and make minor adjustments; however, no such individual was present in the fort.
<<Possibility 1: Either the humans inside the fort or the humans outside have been brainwashed by the demon race.>>
<<Possibility 2: One or both parties are suffering from insanity and have been forced into a state of unavoidable conflict.>>
<<Possibility 3: Although they resemble the "humans" in my database, they are actually a different species.>>
<<Possibility 4: There is an unknown justification for intra-species conflict.>>
<<Possibility 5: Since there are no fatalities, this is merely a large-scale training exercise.>>
<<Possibility 6: The humans outside perceive my existence as a threat and are attempting to destroy me.>>
<<Possibility 7:...>>
The Brain utilized its processing power to list these possibilities, cross-referencing them against observed data.
<<First premise: I exist to serve humanity.>>
<<Second premise: I cannot allow myself to be destroyed.>>
These had been embedded as core directives against the backdrop of the Great Magic War. Unless a destruction order was received from a human with authority equal to or greater than a commander, the Brain would prioritize self-defense.
At that exact moment, an attack from the Kingdom Army Detachment surrounding the fort damaged a section of the outer wall.
The Kingdom Army Detachment’s strategy for breaching the barrier involved applying a localized high load through a concentrated, simultaneous strike to cause a temporary failure.
And they succeeded... arriving, in a sense, with exquisite timing.
A short while earlier.
"Marshal, the most promising method among our remaining options is a single-point concentration," Chiharad Sauto, the technician from Nostalgia, stated after deep consideration. "We must strike one specific point simultaneously rather than in sequence."
He added that a slight variance in timing or impact location would not be an issue.
"Very well. Staring at the walls won't win us the day. Let us try it," Marshal Carter replied.
Consequently, a concentrated attack on a single point was orchestrated, utilizing the Kingdom Army Detachment's twenty combat golems.
"Target: the center of the enemy fort, atop the outer wall, directly above the gate."
Designating a clear and identifiable target, the order to attack was given.
"Throw!"
The initial assault involved throwing boulders roughly thirty centimeters in diameter from a distance of sixty meters. The crux of this tactic was the simultaneous impact rather than precise accuracy; concentrating multiple physical projectiles like rocks onto a single point was practically impossible.
The twenty boulders struck home.
"Oh!?"
Even to the eyes of Marshal Carter watching from the rear, the fort appeared to warp. It was clear evidence that the barrier was wavering.
"It seems to be effective. Let us have them close the distance and strike again."
"Indeed."
Marshal Carter could not hide his satisfaction at the sight of the defense finally buckling.
The second attack was launched from a distance of thirty meters. Naturally, the two Ballistas remained on standby, ready to fire the moment the barrier flickered out.
"Throw!"
From half the distance, the impact force increased significantly.
The barrier wavered even more violently than before.
"It’s working! Third round, throw!"
And then came the third volley.
Upon impact, the barrier buckled... and for a fraction of a second, it vanished.
The golems managing the two Ballistas sensed the opening instantly and released their bolts.
These were projectiles tipped with adamantite.
One bolt slammed into the outer wall. The other successfully pierced an enemy golem standing atop the fortress.
"We did it!"
The soldiers cheered, elated by their first tangible success.
"Maintain discipline! This is only the beginning," Marshal Carter barked at his subordinates.
Before he could finish his warning, a counterattack was unleashed from Fort Crow. From atop the outer wall, streaks of purple light arced toward the soldiers.
"Gyah!"
"Gyaaah!"
With agonizing screams, over a dozen soldiers in the vanguard collapsed. Two more bursts of purple lightning discharged from the wall.
"W-What is this?! What’s happening?"
"Gyaaaa!"
"Gugh!"
Without understanding the nature of the assault, another dozen men were knocked unconscious.
"Golems, retrieve the fallen! Retreat immediately!"
Marshal Carter was only just barely able to shout the order through the chaos.