euskal34
- ctf
- reversing
- cryptography
- python
Euskal Encounter has been setting thirteen challenges a year across its two contests for decades, and the person who used to publish them no longer attends. We won this year, so we wrote them up ourselves.
They come as two chained series: seven levels of logic and cryptography, six of reversing and hacking. You can’t even read the next problem statement until you solve the previous one, so every stall blocks the whole queue. We finished first with twelve points out of thirteen, tied with another team and ahead of them on solve time.
The challenges had a bit of everything: a Linear Elamite inscription that turned out to hide Norwegian describing a place from The Silmarillion, a Pokémon ROM carrying a message written in the tactile system Barbier invented before braille, a Brainfuck interpreter inside a Mega Drive cartridge, and a 394 MiB audio file that was really a VHS video tape.
What interests me most about the repo isn’t the solutions, it’s the dead ends. They’re all in there, named, with the hours they cost. A writeup that only shows the straight line lies about how this actually gets solved, and five of the twelve we published say outright what was left unfinished.
How it’s built — Python · signal analysis · m68k reversing · AI-assisted from start to finish