By its co-founders, Amira Bouguera (cryptographer) & Sajida Zouarhi (blockchain architect)

Abandon all hope ye who enter here.


Once upon a time, there was a place called Earth where people were living in happiness and peace until one day they discovered a magical power called the “Internet”.

And that is when all hell broke loose…

The Internet came along to allow people to connect to one another and exchange information no matter where they were in the world. Some saw the potential of this new technology and wanted to use it for good and some others: well… they had ulterior motives.

A monster, created by some nefarious people using the Internet, started sucking humans’ souls, one by one.

Souls = private data

Humans became more and more connected to various devices (mobile phones, computers) and addicted to social media, while the monster was continuing to grow, feeding itself with their personal information…

In these dark ages, a force was at work, trying to restore the balance that humanity lost.

Surprisingly enough, hope came from the least expected place: the Underworld.

That place was a lot less scary than it used to be in our mythological books.

Hellhounds, the creatures living there, finally got rid of Hades and now operate in a decentralized fashion.

Hellhounds want to serve humans in their own way, as humans are doing such a poor job on Earth protecting themselves…

However the challenge about protecting humans souls is protecting humans from themselves.

As it turns out nowadays, the closest thing to someone’s soul is their data.

That gave the HellHounds a purpose, a mission.

Introducing HellHound

In human language, HellHound can be described as a decentralized blind computation platform.

The hellhounds work as a pack to provide a computing environment that uses a set of cryptographic powers to enable humans to implement privacy-by-design in their dApps.

Cryptography is the hellhounds superpower. Another ability they were gifted with, is to work together in a decentralized way through their own language: HOWL.

Hellhounds are committed to serve humanity but they are not really … human friendly.

To succeed in their mission, they can count on:

  • Cerberus, a loyal companion that is friendly enough for human to trust him and close enough to the hellhounds to communicate with them using the HOWL.
  • Pythia, a seer that helps humans make better decision through her knowledge.
  • STYX, a creature which can never break an oath and is older than the hellhounds themselves.

Devcon IV Experience

As you may have noticed by reading the above explanation, HellHound is a combination of a fictional universe and a technological one.

We decided to build a bridge between these two different worlds and instead of delivering a traditional technical workshop about Privacy and Cryptography, we built an Escape Room for Devcon IV.

Stay tuned for our next blog post where we will explain this game in detail, disclose the complete ranking of the teams who participated, share some anecdotes and announce the winners who managed to escape from the Hellhound Underworld.

HellHound Escape Game

Enter the Game and learn how to play!

The goal of this Escape Game is to discover basic and advanced cryptographic methods while having fun. It is also an opportunity to learn more about the HellHound protocol our team is building: a network of hellish nodes performing blind computation over encrypted data for applications.

But first, why an Escape Game?

Escape Games are perfect to make people want to simultaneously curse you and high-five you.

We wanted to successfully engage with the participants at Devcon IV and create an unforgettable experience for them and for us. We also wanted to make complex concepts less scary so that people feel empowered exploring this universe.

It turns out that what you need to successfully break out from an Escape room fits the cryptography and hacker mindset. An appetite for riddles, puzzles, mystery and challenges …

Simple Game play

  • The participants evolve step by step within the HellHound universe.
  • Each step requires solving a challenge. To reach the next step, you must solve the challenge of the previous step.
  • Each challenge is an opportunity to learn something new about cryptography.
  • Each challenge is a chance to work as a team to maximize your efficiency, like the hellhounds do.
  • The story around the steps and the challenges enables the players to understand how HellHound can be used by developers. The characters of the game are the Core Components of Hellhound (Pythia, Cerberus, Hellhounds and STYX).

Time to play. Go to hell and come back (alive).

How: Solve the cryptographic dilemmas.

Special powers: Mathematics and teamwork (reach consensus and do it fast!).

Rule: Be aware of the malicious Hounds!

Goal: Save Vitalik’s soul and your own…

Stage 1: Free Cerberus from his Prison

Story goals:

The goal is to unlock your companion Cerberus the three headed dog, and get him accepted by the pack of HellHounds living in the underworld. If you succeed, Cerberus will guide you through this journey.

Technical explanations:

Cerberus is a user-friendly client. The UX with Cerberus is easier and smooth, it allows the user to interact with the hellhounds network.

Stage 2: Summon Pythia

“Pythia is an Oracle. If you are in need of information, you can summon her and seek guidance. Remember, Pythia is BLIND to human foolishness.”

Story goals:

  • Cerberus has to be accepted by the pack of HellHounds.
  • Successfully summon Pythia.

Technical explanation:

Pythia is the recommendation engine, her purpose is to provide the best advice to the human, but the human needs to know what she is looking for or Pythia can’t help.

Stage 3: Don’t Be Fooled

To find the Betrayer, you will need to listen carefully to what Pythia says.

Story goals:

  • Protect your companion Cerberus from zombie dogs pretending to be HellHounds.
  • Fight malicious nodes (zombie dogs).
  • Prove that the network is resilient to malicious nodes since the correct result is recovered at the end.

Technical explanation:

Zombie hounds are hidden in the Underworld. They are potential dishonest (or honest but curious) nodes on the network. We have two types of attackers — passive and active attackers. The passive ones are curious and the active ones are betrayers changing information and sending false results.

Stage 4: Working With the Pack

Story goals:

Now Cerberus must work with the pack of true Hellhounds to find Vitalik’s soul.

Technical explanation:

Hellhound nodes are part of a computation network, they work together to perform calculation, if they are not honest they are punished. They need to go through the Purgatory process to be considered a Hellhound. Secure Multi Party Computation between HellHound nodes and Cerberus.

Stage 5: Get The Hell Out!

“Humans, we have one last mission in the underworld…

Free Vitalik’s soul. If you fail, his soul and your own will be condemned to eternal damnation.”

Story goals:

  • Find the last word to open the gates of the underworld and set themselves free.
  • The Styx owns Vitalik’s soul

Message from the STYX

“Soul = VITALIK;

Soul.owner = STYX;”

Technical explanation:

The Styx is a suite of smart contracts that represents the on-chain world (blockchain).

In order to save Vitalik you must transfer ownership from the Styx to Vitalik’s public key.

Congratulations! Soul ownership was transferred successfully.

An oath with the STYX is irrevocable, even for the Gods.

Since you made it through the rings of Hell, you may now go back to the mortal world with Vitalik’s soul.

Go forth from Hell, but speak not of what ye have seen here, for the Styx is forever watching and will hunt ye down if ye do.

Leave the underworld. Now!







You are still reading the post? We said leave ………Now!

Follow HellHound:

Stay tuned for the other pedagogical and fun experiences on complex topics we intend to create.



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