The Archive

Nihilist on the rail

Hard. Nihilist: Polybius numbers plus a repeating key. Key RAIL. I/J share.

Fraction on the pad

Medium–hard. ADFGX. Five-by-five fractionated Morse-style grid, then the pairs as letters A D F G X.

Flags on the pad

Easy. Semaphore. Flags as clock positions, letters A–Z around the circle.

Digits on the invite

Medium. Gronsfeld. Like Vigenère, but the key is digits. Key 2014. Spaces honest.

Bifid in the factory

Hard. Bifid cipher. Keyword TESLA, period 5, I/J share.

Beaufort on the Gulf

Medium. Beaufort cipher, keyword STAR. Same operation encodes and decodes.

Autokey from the rail

Hard. Autokey Vigenère. Primer RAIL, then the plaintext itself becomes the rest of the key. Spaces stripped.

Three ships, three places

Harder. A tiny logic grid. This week’s Starship traffic.

Three rungs to steel

Easy. A word ladder. Change one letter at a time.

Taps from the tower

Easy–medium. Prison tap code. Five-by-five, I and J share.

Star key on the Gulf

Medium. Vigenère. Keyword STAR, repeating.