…wow, okay then. Maybe she should avoid picking rock in the game where the rule is that her opponent is only allowed to pick paper, hmm?

Come to think of it, he did say that her problem was only evaluating her own hand and ignoring Chloe Zell's. Maybe she'll try to learn from her mistakes for once. So, what does Sora think about this game?

If Sora plays paper, he has a fifty-fifty chance of winning. Or a one-in-three chance each of winning, losing, or going to a rematch; Stephanie still isn't sure how to do the math on that properly. She's absolutely not going to choose rock, so for now it's probably best to think of it as a two-in-three of 'not losing'.

But he can only choose paper, per the handicap. If he chooses rock or scissors he has a 100% chance of losing, with only a one-in-three chance of Stephanie losing too.

It doesn't make sense for Sora to choose anything other than paper. That's the mind game right there: make it seem like there's a mind game and twist Stephanie into knots before choosing paper, exactly like he said he would.

When she thinks of it like that, the solution is obvious.

Both players raise their fists and speak in unison.

"Rock, paper, scissors!"

Scissors!

Rock.

"Not bad, Stephanie. I saw your face; you almost let me get you to throw rock, didn't I? Good job avoiding that. By not choosing rock, you prevented me from winning the game."

He sounds genuinely effusive with his praise. The smile on his face is sincere.

"Still, you should've chosen paper. That's what would've maximized your odds of winning the game yourself."

"What are you talking about? Scissors gave me a two-thirds chance of winning, and paper only gave me half that! Scissors dominates paper as a strategy!"

"And I knew that! I picked the rules, I set the probabilities, I told you what to think! You believe this is a game of mathematics and chance? Wrong! This is a game of reading your opponent."

Shiro rolls her eyes. All games are games of mathematics and chance. She won't say it though – it'd detract from the lesson that Sora is trying to teach.

"You ruled out rock, which was half of a winning plan. If you'd thought about why I made the rules the way they were, you'd have understood enough to finish the other half: ruling out scissors, the safer option with better odds that I handed to you on a silver platter."

"I— you— fine, whatever," Stephanie splutters. "You were trying to force a tie anyways. Can you tell me what the cell phone does, now that I own half of it?"

Shiro hands her the cell phone.

"It's an extremely powerful computer and communications device. The communication network it relies on is not present in Elkia, but outside of that it's capable of performing certain tasks better than humans. Much better than humans – providing numbers for comparison would be pointless. It stores thousands of local copies of books, images, audio, and various combinations thereof, and it can defeat anyone alive at games in inverse proportion to how much luck is involved. For games of pure strategy it's orders of magnitude stronger than is theoretically possible for humans."

Stephanie looks down at the cell phone as though she has been handed the nuclear football.

Sora rolls his eyes.

"The chess engine on that thing is good but not perfect. We don't know everything the people on Disboard are capable of, so don't count on it if your opponent happens to be a robot or something. It can only play games we tell it how to play, and giving it new games to play will take Shiro and I working together for at least a few days each. It also runs on a form of energy that we have no easy way to replenish, so the plan is to ration its use until we can fix that."

He didn't ask the concierge whether Elkian chemists had managed to purify copper and zinc, but on the off chance they have he can get a voltaic pile set up on relatively short notice.

"It's not magical?"

Stephanie examines it closely. It's a thin rectangular prism, smooth metal and glass, with two buttons on one edge and a third on the opposite edge. The surface is a black mirror.

Sora reaches over and presses the button on the side. His lock screen is a digital photograph of himself and Shiro taken eight years ago, glaring at each other across a chessboard. He taps the bottom and the screen overlays a grid of nine dots. He swipes through them in a pattern and the phone unlocks, showing the note he typed out earlier.

"That's how you activate it if it's sleeping. If it's off, hold down the button. The pattern I showed you is a secret, to prevent unauthorized access." He closes the note. "The icons here are called apps. This app is the library. This one is chess. This one is a poker odds calculator. When you asked earlier whether I used this to detect cheating and I said it was possible, I was referring to books in the library."

He demonstrates. The library is filled with an obscene number of books, none of them in languages that Stephanie can read.

Stephanie absorbs this. The cell phone, of which she is now co-owner, is plausibly the most valuable object in the entire kingdom. Even foreigners would want it badly, if they knew of its existence. Humanity is uniquely handicapped at performing magic, but some of the other lesser races haven't fared much better. A device that can win any chess game… she can think of several places this thing might be needed, some of them acutely.

Speaking of: "You're using translation magic. Where did that come from, if not the cell phone?"

"Won it off a fairy," Sora says brusquely.

"Did you use the cell phone?"

"No one outside the three of us knows of its existence. Unless you count Tet, in which case there are four."

Presumably Tet knows everything, but since the cell phone is not currently relevant to the outcome of a game Stephanie doesn't expect divine intervention. Point taken about it calling Tet's attention if she uses it that way, which she absolutely intends to do.

"Good to know, thank you. As for my end of the deal, there are a few options. I can give you my room here and extend my stay, I can buy you a room in a different hotel, or I can put you up in the castle's ambassador suite. If I tell the castellan you're visiting from Elven Gard or the Eastern Union there won't be any issues. That's likely to be the best option, since it's close to the tournament, but you might want to stay further from the castle if you have other concerns to manage."

"Nah."

"Do you not want your prize?"

"Didn't say that, did I? Actually – hey Shiro, what did I say, exactly?"