I Know The Rules Of Chess

“Do you know the rules of chess?”

The other Shadow Necromancer—Sobra—asked.

He asked whether I knew the rules of chess.

“…Huh?”

If it’s the board game chess, I at least know how the pieces move.

But I don’t know openings or strategies at all, and above all I’m bad at games that use my brain.

Probably, if I taught Rin the rules she’d beat me within the day—I’m that sure of it.

“(Or rather—does he seriously intend to decide a battle whose stakes could be the fate of the world with chess!?)”

Does he really think I’ll accept that condition seriously?

“Whoa—I’m not saying we should decide the winner by actual chess. I’m proposing rules modeled after chess.”

Thank goodness.

If it were chess, I’d definitely lose.

“A Shadow Necromancer is like a commander who controls an army of Shadows—yet, embarrassingly, I’m bad at brainy games, and I’ve never beaten Ruru at chess. Maybe my brain’s rotten.”

“Don’t worry. My brain’s rotten too.”

“So, um… let me explain the concrete rules—”

Sobra explained rules optimized for a duel between Shadow Necromancers.

To summarize—

【Premise】
Chess uses eight small pieces (pawns) and eight major pieces of five types (non-pawns)—six types, sixteen pieces in total.

【Rule ①】
Treat Shadows as the fifteen pieces excluding the king, and simultaneously manifest fifteen Shadows at the start of the duel.

【Rule ②】
During the duel, summoning new Shadows is forbidden, and perished Shadows may not be re-summoned.

【Rule ③】
The piece corresponding to the king is handled by the caster personally.

【Victory Conditions】
Victory is achieved by annihilating the opponent’s pieces other than the king—that is, all their Shadows.

Alternatively, the duel ends if the king becomes incapacitated or surrenders.

――Something like that.

“To add a finer point: the pieces don’t have to be Shadows. Instead of Shadow Necromance, you may use corporeal minions under Necromance.”

In other words—you can use Ekarraat or Vanargand.

Conversely—that means Sobra will also use the Five Great Demon Lords.

“And the eight front-line Shadows that correspond to pawns must be Shadows of the same name.”

‘So the pawns are merely grunts—Sid, do you understand?’

“(Barely managing—yeah.)”

‘Don’t try to sound cool about it…’

So you need to possess at least eight Shadows to use as pawns, right?

That means you can’t use a boss monster that exists as only one in a dungeon; you must use the disposable trash monsters that spawn endlessly when you dive a dungeon.

But—this rule works to my advantage.

I awakened as a Shadow Necromancer about half a year ago.

Sobra, on the other hand, is a veteran Shadow Necromancer with at least twenty years’ experience.

Even though the recent large-scale dungeon collapse allowed him to expand his forces, in both number and quality of Shadows stored in the darkness, he’s probably far superior.

And Sobra is willing to make it 15 vs 15.

Is he trying to lure me into the match by proposing rules favorable to me?

“So—the winner takes the loser’s Five Great Demon Lords, right?”

If I win, I’ll take his ‘Divine Brain Akasha’ and ‘Birthing Kukulkan’—

If he wins, he’ll take my Crimson Vampire Princess Ekarraat and Devouring Vanargand—

――In short, the winner will steal them.

“No—let’s make it one piece.”

Sobra raised a skeletal index finger and continued.

“We’ll be tied together for a long time, Sid. Also, I’m not overly confident I’ll definitely win. If I lose here and you end up with four of the Five Great Demon Lords, my chance of ever beating you again would be zero.”

“You’re surprisingly timid.”

“That stings, but say what you want. I’m a coward by nature—however, if I win, I’ll take Ekarraat.”

‘So it’s two men fighting over one beauty—Sid, if you don’t want me stolen from under you, you better fight seriously, yes?’

I wanted to retort to Ekarraat’s nonsense, but something else bothered me more, so I ignored her.

Ekarraat’s power is to make others immortal and ageless.

And Vanargand’s power is spatial transfer and extradimensional storage.

I didn’t understand why Sobra, who already has an undying body as a Shadow Necromancer, would prioritize Ekarraat over Vanargand.

“Why Ekarraat? You’re already immortal, aren’t you?”

“There are kinds of undying bodies. In my case I awakened after consuming an Undead elixir—an A-rank dungeon boss drop. But that only makes you immune to disease, stops aging, and speeds healing a bit—it doesn’t grant regeneration like yours, where the body restores to its prime and missing limbs instantly regrow.”

“……”

“When I was defeated by the Holy Church twenty years ago, I was on the brink of death—I spent ten years just healing. And it’s hard to call it a full recovery—I’m still left with nerve paralysis in my limbs and can’t walk properly.”

Sobra remained seated on the throne the whole time.

It wasn’t that he refused to walk—he couldn’t.

It made sense that, despite having Shadows, he kept the living human Ruru as a subordinate—he needed human hands and feet to gather information for him.

“Originally I planned to slip Ruru into the Hero’s party and have her bring back Ekarraat’s blood, but before Ruru could collect it, Sid stole it.”

“So you want Ekarraat’s blood to gain a stronger form of immortality.”

“Exactly—Vanargand’s ability is tempting, but the Shadow by my side, the demon priest Barom, can use teleportation magic; it’s a lesser substitute, but it’s sufficient for now.”

Sobra pointed with his thumb to the goat-headed Shadow waiting on the opposite side from Ruru.

“So—will you accept this duel?”

“Before that, one thing I’ve wondered the whole time—how did you find my location? Have you been watching me all along?”

“Ah, that—you’re aware of the large dungeon collapse that happened in the capital last month, right?”

“Yeah.”

Sobra continued without raising his voice, as if it were no big deal.

“I was the one who caused it.”

“…What?”

“I had traced Sid’s location to a hideout in the Goblin Forest, but then I lost your trail, so I triggered the dungeon collapse to lure you out.”

Sobra continued.

“Then—when you casually showed yourself there, Ruru approached and had a ‘mark’ implanted on you.”

“A mark…?”

“It’s like a magical device to track the target’s location.”

When did that happen…?

I dug through my memory.

Now that I think about it, I remember helping a taciturn mage.

Could that mage have actually been Ruru in disguise, who planted the ‘mark’ somewhere in my long coat then?

“You put the capital in danger just for that—just to seek my location?”

“Well, to be honest, I did have a bit of a desire for revenge. I wanted to kill the Holy Church that made me into this body.”

“Isn’t that originally because you tried to overthrow the state?”

“Now—since your questions are answered, let’s get back to the point. Will you take the duel? I’m tired of sitting on this throne forever.”

“……”

From my perspective, I’m not interested in collecting all Five Great Demon Lords to become the creator god of a new world.

But I want to avoid being harassed forever for having the Five Great Demon Lords in my possession.

So it makes sense to accept a duel under rules favorable to me, grab one of the Five Great Demon Lords, and weaken his forces.

To add a personal grudge: the Shikai Tribe were treated as heretics and many Shikai, including my hometown, were massacred because this guy rampaged using Shadow Necromancer powers twenty years ago.

For the sake of avenging my kin’s humiliation, I want to kill him.

“Fine—I’ll fight under those conditions.”

“I thought you’d say that.”

Sobra laughed arrogantly on his throne.

A smile certain of his victory.

“Then let’s begin――――the Shadow War!”

To shatter that smile, I immediately set about arranging the fifteen pieces to use in the duel.