(Edit: This was in large part prompted by looking at the rolls details and seeing just how fucking pear-shaped things went for the fleet between the 2nd and 3rd rolls, and also poking some fun at Imperium bombast)
xxxx
Upon the command deck of a Dark Eldar cruiser which had been preying upon the void lanes back when the Eldar strode the Galaxy, united and implacable, before She-Who-Thirsts, before the Eye of Terror, before the ascension of the Chaos, before all these trillions of mon-keigh infested the galaxy like so many lice on an unwashed pit slave's back hair, a tall Archon sat. She was drumming her fingers upon a part of the upholstery on her command chair that had once gone by the name Magnus, and listening to the sensor reports.
"Repeat the sensor sweep," she said. "And make more sense than your predecessor."
The luckless Kabalite officer glanced down at the dismembered figure at his feet, then back up at his Archon, all glad in black leather and plates of twisted metallurgy. "Right away, master," he replied. Soon after, he came back with the results. "The ... uh, the ... umm ... the prey fleet is ... well, it's what they look like. Mon-Keigh crews, fleet composition is ... basically Imperium norms."
The Archon looked over at her technician with a nonplussed expression, lips pursed sourly. She glanced at her plot board, the casualty lists, then back up at the technicians.
A few minutes later when the fourth technician repeated the same report, she decided there was no point arguing the inarguable and let this one live. There was a battle to knuckle down to, no matter how baffling it was. This Mon-Keigh admiral could made for a junior corsair Archon. It was staggering! She didn't think they lived long enough to do that.
"Humph, well then," she said. "Time to start taking this more seriously. ... and not a word out of you, Dracon. Yes, the first two waves consisted mainly of my political enemies, but even they shouldn't have been bested by this filthy vermin fleet. Very well, let's show them what a true Eldar fleet at war looks like. And intensify the anti-Psyker Wards, I smell witch-work at play here."
xxxx
"Well, that's two waves down, how many more?" asked Admiral Freyr on the bridge of his battleship. The rings of Fjol V wafted past gracefully outside, displayed on giant viewscreens on the bridge.
Ridcully twitched. "I'm ... huh. It's not so clear as the last two times. But there is a third wave coming, prepare yourself. I'm just not sure exactly where..."
"Admiral!" shouted an officer from down among the technicians. "The Grand Cruiser Fist of Piety is exploding, sir!"
Freyr glanced down at the Avernite diviner on his bridge. He pointed towards the sensor display and cocked an eyebrow.
Ridcully coughed into his hand. "Yes, that would most likely be the third wave now."
"Of course, thanks for the timely warning," said Freyr, glowering at the psyker.
"Hey, I bailed you out on the last two waves, can't expect me to get them all," said Ridcully. "Don't worry, I can get you into a great spot for the fourth wave. And on the bright side, I can foretell that when you see the logs of this last ambush you are going to learn some amazing things about ambushes that will really help us in decades to come."
They watched the sensor board in silence, waiting for a pattern to appear that Freyr could intervene in as his subordinate commands redeployed their ships with a drilled precision far beyond that of most Imperium fleets. And it was just as well, as the wave of destruction that washed over them would have utterly annihilated any other Imperium fleet of their size. As it was, the Dark Eldar quickly avenged themselves of the "easy" bloody nose he had given them in the first two waves.
"Say what you will about the Dark Eldar," said Freyr as explosions and fire rippled across the Fist of Piety rhythmically. "They do know how to make things explode artfully. Of course, as for myself, I just want to see foul xenos blown to flinders in as ugly and graceless a manner possible. Do you have my target coordinates yet, Ridcully?"
"I certainly do, Admiral, transmitting now. And brace yourself, this is about to get stressful."
"Oh, right, like the first two waves were as easy as the nobles of Vanaheim."
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Ten years from now, in a lecture theatre with a very bored Governor's Daughter.
"Children of Avernus," barked the instructor at the front of the lecture theatre. "Today we learn about the glorious Naval Battle of Fjol IV, where the blessed forces of the Nine Worlds slaughtered the Dark Eldar xenos and drove him and all his works before the justice that the Emperor would see turned upon all Xenos. ... uh, except for our Quartok friends. Turn your textbooks to page one thousand, five hundred, forty seven."
Syr, looking ever more and more like her mother's younger sister and growing increasingly concerned that if rejuve technology got any better she'd begin to look like Lady Freya's older sister, sat in the back with her regular companions looking bored. "I've been dreading this day," she muttered.
"What? You normally love the lessons about battles?" asked one of her companions.
"I read ahead through the textbook, I know how much the quotations are almost entirely fabricated," said Syr.
"How could you know that?"
"Dad let me listen to the actual logs so I understood what facing a dangerous foe was really like," said Syr. "Like this passage..."
'And lo, the third wave of the foul Xeno assault came bearing destruction in the form of all the vile artifices of their kind. Yet even as the cowardly assault broke upon the shield of the Fleet, less devout hearts quailed. So it was that Solar Admiral Freyr drew his sword and pointed at the enemy cruisers, saying, 'Though the Xenos bring forth fire upon fire, do not despair, for you are the wrath of the Emperor and the Nine Worlds!' And thus the battleships smote the flimsy constructs of the enemy, annihilating in the final exchange before planet fall two insidious Xenos cruisers, for the paltry loss of a Grand Cruiser, nine Battlecruisers, six cruisers and thirteen Light Cruisers.'
"The actual quotation...," said Syr as she dug up a slate and found a document. "Ahem, 'Emperor's Grace, even the explosions are exploding! It's nastier than an Anvernus petting zoo in here. Throne-dammit, you scrotumless dogs, comms, tell Admiral Telemacharite that if doesn't get forward into the teeth of that fight I'll have his guts for garters! By the Emperor, Ridcully, give me targets now or use your divination to figure out where I'm about to stick my fist!'"
"I always figured the standard of classical rhetoric in the history books was suspiciously high," said her friend.
"Also, there's a bit in there about dad exhorting uncle Freyr to stiffen his resolve on the flank, that was actually dad freaking out when an escort next to his transport blew up, and threatening Uncle with the Avernite wildlife Mom was going to send him in the mail if Uncle got him killed."
"Is ... is it heresy to know this stuff?"
"Just perks of being the Governor's brat."