This is an archived problem from a previous year. Submissions are closed, but you can view the problem and its solution.

30

Placement mate

With the puzzle solved, the door unlocks, and the group steps into the restricted section. The air feels thick, charged, like a storm is about to break. As you move further in, ghostly images begin to flicker—elves working, schematics of old designs, even glimpses of chessboards mid-game.

Magnus stops in his tracks, staring at one of the flickers. "That’s Alekhine. I’d know that game anywhere - it’s his 1929 match with Bogoljubov. But how is it here?"

David frowns, watching another image fade in and out. "These aren’t just images. They’re... echoes of the past. Spacetime must be warping under the interference. The TSC is bending reality in this area."

The group presses on, and the apparitions grow more vivid. At one point, a shadowy figure appears at the end of the corridor, standing motionless. "Is that... Garry Kaspelf?" Wesley whispers.

Magnus steps forward, but the figure vanishes, leaving only a faint glow where it stood. In its place, a chessboard appears, the pieces arranged mid-game.

David points to the board. "Another puzzle. Solve it, and we might get closer to figuring out what’s happening."

Wesley reaches to move a bishop, but it doesn’t budge. "It’s stuck?!"

Magnus leans in. "This section was sealed off years ago after an experiment went wrong. Guarded pieces have been locked in place ever since. You’ll have to work around it."

In this position, any piece protected by another piece of the same color may not move. A pinned piece, however, does not function as a protector, because it cannot move. That means that you can move a piece that is only guarded by pinned pieces. White to mate in 2. If anything is unclear, ask in our Discord.