"Alright, kid," said Cheis, putting down her cup of coffee.  "It's time to shit or get off the pot."

 Linduin, a spoonful of porridge halfway to his mouth, paused.  "Excuse me?"

 Cheis gestured vaguely.  "You've been cooling your heels here for two seasons now.  You've read all my math books, cleaned everything I own a hundred times.  It's spring now.  What are you waiting for?"

 Linduin frowned.  "You said you wouldn't teach me magic until I impressed you.  I, um, thought this was all a big test.  I thought it'd be years before you really gave me a chance."

 Cheis sighed.  "Either you're an even bigger idiot than I thought -- which, I really must say, is impressive -- or you're trying way too hard.  Either way, you're testing my patience."

 "I am?"  Linduin blinked, perplexed.

 "Cast your tiny, dirt-covered mind back a while.  You might remember that I gave you a test.  You chose to weasel out of it by putting it off."

 "Huh?  Oh, right, with the rock."  Linduin dug around under a counter and proudly produced the object in question.  "See, I haven't forgotten.  I even saved it."

 Cheis nodded.  "Six months is a long-ass time to decide whether to obey a command.  Get on with it."

 Linduin, wincing, set the rock down on the table carefully.  "Okay.  I still wanted more time to check my answer, but I think I've got it."  Fetching his writing slate, he began drawing the symbols for a logical analysis.  "The specific components of the command were 'hit yourself in the head with it as hard as you can', where 'it', was unambiguously identified as this specific rock."

 "Yeeeess....?"  Cheis wasn't sure where this was going.

 "So." Linduin expanded his symbolic analysis into a branching graph of decision tree nodes.  "In a blind obedience model, both of the two basic paths -- refuse, and obey -- terminate in a failure with ninety-nine-plus percentage confidence, based on iterated analysis of unknown pass/fail tuples.  So we need a third path."  He divided the nodes into two sections with a dotted line.  "On the left, we have 'refuse plus' where we modify the refusal with a subordinate clause or some other type of modification.  But all of the available options for modification are either semantic -- " he crossed out several nodes " -- or are not otherwise meaningfully distinct from the basic refusal path."

 Cheis, who was not looking impressed, said nothing.

 "So, from there," continued Linduin, now beginning to sweat and feeling increasingly foolish, "we expand on the 'obey plus' options, where we have a lot of similar cases, but a couple of promising ones that don't end with guaranteed failure.  There's the 'obey with trust' path you suggested back then, which --"

 "If you're going to go into game theory," interrupted Cheis cheerfully, "you can pack up right now."

 "Of course not", managed Linduin, rather hurriedly turning the decision matrix he had been drawing into a set of smashed-together addendum reference symbols, "but let's just note that those don't resolve into anything that the base options didn't.  Which leaves us with only a couple of possible choices."  He circled the remaining handful of nodes.  "Now that we have our field narrowed, we can calculate the key factors that will distinguish them.  If we express the original command as a --"

 Cheis cracked her knuckles.  Linduin froze, looking back at her out of one terrified eye while the other kept checking his existing work.

 "Enough stalling." growled Cheis.  "Let's see your implementation."

 Linduin sighed, bent down, and picked up the rock in his right hand.  Then he picked up a large wooden bucket with his left, flipped it rather deftly over his head, and smashed the rock directly into his own face.

 The large, heavy stone struck Linduin's head with a highly respectable thousand or so newtons of force and was diffused and mitigated quite nicely by the bucket, its oaken planks expanding and migrating the force out over the whole of his face in what ultimately culminated as merely a stinging smack of wood across his nose, cheekbones, brows, and other protruding topographical structures, turning an impact that would have been savage and possibly injurious into one that was merely obnoxious.  However, the total amount of momentum, almost entirely unchanged by the bucket, was still more than sufficient to overcome Linduin's balance.  He stumbled backward, tripped over his chair, and went ass-over-teakettle into the kitchen's stove.

 The stove, which had been used very recently to cook breakfast, was both still quite hot and covered with pots and pans.  The resulting crashing, screaming, fumbling, and collapsing was both extremely loud and very painful for Linduin, but the noise was easily exceeded by Cheis's braying, hysterical laughter.

 "You...you...you... ahahaha", was all that she managed for many minutes.  When, finally, the whooping howls of glee managed to subside enough for her to draw breath, she glanced up at Linduin's bruised and sorrowful face, saw the porridge dripping out of his hair, and was set off again with even greater intensity.  She managed to scramble to the bathroom amidst further paroxysms of hilarity before she wet herself, but it was a very near thing.  Linduin, near tears, looked sadly at the broken remains of his writing slate and tried to figure out where his calculations had gone wrong.  It was the better part of an hour before a red-faced and tear-streaked Cheis, gasping for breath and gulping water from a glass, managed to emerge.

The narrative has been stolen; if detected on Amazon, report the infringement.

 "So," muttered Linduin.  Cheis held up a hand.

 "If you're about to ask 'how did I do' or something equally cretinous, please don't, because I don't think my heart could take it."  She giggled a few more times before managing to maneuver her way back into her chair, took another sip of her coffee, and let out a sigh of satisfaction.  

 Linduin, his pride and hopes rent asunder, couldn't find words.  Finally, he settled for an embarrassed apology.  "I'm... sorry.  I was really stupid to think that my solution was the right one.  I just... you know... thought that this technically complied with the requirements, and... um..." he trailed off, wishing he could die outright from mortification.

 Cheis nodded, looked around for a moment, and picked up the remains of the writing slate.  Murmuring a repairing enchantment, she traced one finger down the cracks and stitched the two snapped halves together again, then tossed it breezily at Linduin.  "Here you go."

 Linduin blinked, confused.  "What?  What's this for?"

 Cheis raised an eyebrow.  "I don't give partial credit.  A functional demonstration of how to cheat like a bastard while still solving the problem is nice and all, but you still need to show your work for it to qualify as a general solution."

 Linduin's mouth flopped open and closed.  Then, unanticipated, a big goofy grin spread across his face.

 ***

 The war machine of Dans-Inuth did not mobilize quickly or cleanly.  What soldiers it had were mostly conscripts or bullies with a thin veneer of legitimacy; the dire impetus of demonic invasion prompted the greater forces of the district to reinforce their ranks, but not by much and not with the most fearsome of warriors.  Each link in the chain of command, keeping at least one-and-a-half if not two eyes upon their own concerns, found deftly creative ways to meet the letter of the king's decree with minimal expenditure.  And so it was that when the assembled forces of humanity and civilization finally managed to mount a response to the swarming spawn of the Black Oak upon the fields between Dray's Hill and Sweetbough, the results were less than inspiring.

 The marshal had hoped for five hundred men; he'd gotten less than half that.  He'd had to threaten to decapitate two nobles to get his hands on any siege at all, and only two of the three mangonels he'd managed to acquire had survived the march intact (and one of those was making lots of worrying creaking noises with every stone it threw).  He had almost no cavalry either, but he decided that that had been a stroke of luck after discovering that horses screamed hideously and kept trying to bolt when in sight of the enemy forces.  Prudently shifting his command post towards the rear of the formation, he sent the signal to attack.

 The weapons of the soldiers were not wholly ineffective; even a tentacled horror dies if you manage to sever whatever weird systems pump ichor around in it, and the igg had been thoroughly unprepared for the advent of ranged firepower.  Arrows and siege stones had decimated the ranks of its brood painfully during the opening phases of the engagement, and things had looked very promising for the first ten minutes or so.  It wasn't until the pikemen started massing for a charge and were abruptly sent flying by the eruptions of dirt-covered burrowing monsters that things really started to go to shit.  Then the second wave of infantry crashed into the soldiers' lines, and the skirmish became a slaughter.

 One young hoplite, splintered shield and rusty sword covered with gore, stumbled and fell as a bull-headed creature with four feathered wings in lieu of arms crashed into his unit, stomping two of his squadmates with powerful hooves and biting the head off a third without pause.  The soldier screamed and voided his bowels, looking upward at what was certainly his doom.  Or, at least, it would have been, had at that precise moment a silver-headed spear not struck swiftly from the side into the bull-demon's left eye.

 Without an instant's hesitation, the spearhead retracted, slashed the creature's throat, then executed a precise series of stabs downwards into its chest, stomach, and groin.  This proved exceedingly prudent, as this particular configuration of biological madness kept its executive functions around the same place as a human body typically contained a spleen.  The demon collapsed into the dirt, spewing foul-smelling humours, and Galar Kayle stepped over its corpse and offered his hand to the fallen soldier.

 Where the line had moments ago been wavering, a knot of steel began to form around the center.  Galar shouted instructions, rallied small squads of survivors, and mobilized them to shore up weak points in the army's defenses.  Though the oakspawn had seemingly insurmountable advantages -- great strength and speed, fearsome natural weapons, unpredictable biology, and overwhelmingly superior numbers -- Galar was quick to note their weaknesses and exploit them.  They were not sound strategic or tactical thinkers; they could be easily baited into chasing after a lone soldier, even one on horseback capable of outrunning them.  They had almost no ranged capability, and were helpless in the face of anything which prevented them from closing into melee combat.  Despite their multivariate anatomies, their critical organs were still mostly stored in one of a small number of vital spots, so proper tactics could still bring them down reliably; and most importantly, they had virtually no sense of self-preservation, willingly surging into fatal circumstances without hesitation as their objectives and instincts directed them.  A keen eye could spot these deficiencies; a battle-hardened veteran's instinct could devise battlefield countermeasures; and a savvy tactical and strategic mind could impart these countermeasures quickly and efficiently to the force it commanded.  Galar Kayle had all three, as well as a burning thirst for vengeance upon the evil which had destroyed his life, his home, and his family.  No oakspawn which came near him escaped.

 For his part, the chief marshal commanded brilliantly. He adapted quickly to the situation, expanded and built upon Galar's efforts, and used him as a spearhead to stitch together bold and unique strategies which avoided defeat time and time again.  In other words, he utilized the forces at his command as well as anyone could possibly have done -- and so when, in the end, he was forced to retreat with barely fifty wounded and traumatized survivors as the horde blackened the earth and swarmed on towards its next nebulous goal, the despair and frustration he felt had a keen tinge of unfairness to it.  At his side, Galar Kayle watched the Black Oak and its forces stream away towards the horizon with fierce hunger and rage.  For him, the war was just beginning.