Minerva's mate

A few days later on December 10th, 

"Hey Mimoko! Wanna hear a little secret?" Daria grinned as Mimoko prepared to head off to school.

"Why are telling me now instead of before?"

"Cuz I was just too focused on our game. Anyway, there's a super secret daily puzzle today with a huge prize pool, but only if you attempt it in-person at a secret puzzle cafe."

"I see. I'll inform the club of it."

...

As evening rolled around, the chess club all gathered at the secret puzzle cafe in Lagoon Pathways.

"Ah, so you've all come. Now for this puzzle, we're granting an additional 2007 bonus points as well as a special badge if you can solve it. Shall you attempt it?" Himitsudono asked.

"We didn't all come out here for nothing," Iori scoffed.

"Then to the back. This one is to be of the utmost secrecy. Your only hint is that you must make something special happen in two moves. And just so you know, not one soul has managed to solve this puzzle yet, and most of them were grandmasters, including Grandmaster Morphy."

"Peter couldn't solve this!? Impossible," Okisato scowled.

"Oh, but given the special nature of this puzzle, it's natural so many good players would fail."

Once everyone was inside their pods, the board and position flashed before everyone. It was White's move, and with pawns on c4, e2, f3, f4, h2, and h3, bishops on c1 and f1, a knight on g1, a rook on h1, and the king on g2 vs Black's position of pawns on c5, d4, f5, and h5 along with the king on h4, it was clear at a glance White was on the verge of winning.

"Peter couldn't solve this? It's mate in two... Hmm, there's two possible ways of mate. Hmm, maybe the less common one, Bishop b2," Okisato thought as he made his move.

"Incorrect. You fail."

"So it was bishop d2, damn it."

However, bishop d2 was not the answer as many members of the chess club tried it, including Mimoko herself, and failed just like Okisato.

Iori meanwhile, was still thinking. "Huh, bishop d2's obvious, but you can also go bishop b2. No way this would be unsolvable if it's one of those, meaning, this has gotta be a style mate. Hmm, only the bishop and e-pawn can move. Ah! En passant!" she exclaimed as she moved her pawn to e4.

"Incorrect, you fail."

"THE FUCK!?"

Another had bitten the dust. Utami soon became the next victim, leaving Yuusuke as the sole founding member left.

"Ngh, it's gotta be some kind of special mate. Only the bishop and e-pawn can move... Bishop e3?" he thought as he made the move.

To his surprise, nothing happened.

"Huh? What's going on?"

"Black to move."

The prompt confused Yuusuke even further. "I have to move for Black now? Er, d takes e3?"

"Correct! You have solved the puzzle!"

Yuusuke's jaw dropped as the pod opened back up. The others looked to be just as shocked until Mimoko suddenly had a revelation.

"Of course... This position. If bishop goes e3, d captures e3 results in not just a stalemate, but a double stalemate. Grr! Okaa-chan got me good!"

"Ohohohoho! Did I now?" Daria giggled as she suddenly appeared, now sporting a drippy sleeveless black kimono with fire embroidery along with a pair of black hi-top sneakers. Her face was still painted as usual, though now her short blonde hair was styled in twin buns.

"Seems like little Yuusuke's just gotten a huge win over every grandmaster out there that's attempted this puzzle, and not just them, other titled players, untitled players, why even his own mom got stumped by this and went straight for the mate. Indeed if this were a normal puzzle, bishop d2 or bishop b2 followed by d3 and bishop e1, mate and bishop e6, mate, respectively, would have solved it. But this is a special puzzle. The goal here was to pull off the elusive double stalemate."

Mimoko let out another anguished groan as she facepalmed. "Himitsudono said "2007", that was the year this sequence was discovered by Enzo Minerva! I had all the hints!"

"Uh, what you talking about?" Iori asked.

"In 2007, Italian chess composer, Enzo Minerva, published the fastest possible way to achieve double stalemate. It's actually a question on one of our trivia quizzes," Himitsudono chuckled. "As for young Shousen, you win not just the point bounty, but a badge for pulling off a double stalemate. And to further add to the glory, you are the first-ever recipient of this badge , or at least the first to get it via beating the special puzzle."

"So I'm assuming the rest of us can get it?" Okisato asked.

"Correct, but only via playing a rated game against someone."

"I'll call up Peter then."