The Skull CTF

by Wokwi

A mind-bending hardware puzzle in three acts

Nov 19, 2020

Completing the Ritual

We're still trying to complete the missing pieces of the Skull's firmware, so we decided to try something radical this week: we hired 256 monkeys, and gave them each a USB typewriter. In order to learn how well that worked, you'll have to click that button down there... Read the full update.

Nov 12, 2020

Eldrich Assembly

You have done it. You have made the world a more dangerous place by successfully funding t́he skull. Nice work. Seriously. Read the full update.

Nov 05, 2020

Blessing the Bytes

First and foremost, the firmware. We've summoned a shaman from the deepest, darkest jungles of a long-forgotten land, and she's been working night and day, performing ancient bytecode incantations to bless our compilers. But our grisly adventures did not end there...and now we need your help with a critical decision! Read the full update.

Oct 31, 2020

Our Campaign is Live. (Happy Halloween!)

This long-forgotten skull yearns for a place on your desk...a place from which, upon waking, it will endeavor to shatter your mind with a horrifying reverse engineering puzzle. Show it you are not afraid by helping us gather enough doubloons to raise it from the dead! Read the full update.

$1,226 raised

of $666 goal

184% Funded!

Pledge Now


The Skull

A single The Skull CTF board (☠)


Two Skulls

A two-pack of The Skull CTF boards (☠☠)


Three Skulls

A three-pack of The Skull CTF boards (☠☠☠)


Pile o' Skulls - Classroom Pack

A ten-pack of The Skull CTF boards. (☠☠☠☠☠☠☠☠☠☠) Perfect for classrooms, workshops, conferences, and very nerdy Halloween parties.


Programmer & Header

Cheat! Or, better yet, design your own puzzles and load them into The Skull's brain using the included SparkFun PGM-09825 AVR Pocket Programmer. Also comes with a ribbon cable and the SMT header you'll need to use it. (Does not include the MiniUSB cable.) Some soldering skill required.


(Early Bird!) The Skull

A single The Skull CTF board (☠)



Wokwi creates tools for the Arduino and maker community, such as AVR8js, the Open source Arduino Simulator, and GoodArduinoCode.

Uri Shaked

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