Nara: Virtual Pet Game for Meshtastic

[eljojo]

What is it?

Nara (Not A Robotic Animal) is a virtual pet game, built as a module for Meshtastic. You battle other nodes and win points.

The idea is to have fun while also encouraging people to join and grow the Meshtastic network.

Watch video here: https://youtu.be/MWfdFIDvkeY

https://github.com/user-attachments/assets/6cd1a610-c8c0-4f2c-8517-1abb95137a72

How to play?

All you have to do is enable the module and go outside!

• Find nodes: You'll start making points by simply finding new Meshtastic nodes.
  • Every 10 minutes, Nara picks up a new online node from the local meshtastic database and invites it to battle.
  • This happens only once per day, per node in the db.
• Battle: If you find another node playing Nara, the two will enter a battle.
  • Naras exchange random numbers, and an algorithm decides who wins.

How does the algorithm work?

The algorithm ensures fair play by using cryptographic hashes to determine winners, regardless of hardware differences.

First, both nodes exchange randomly generated numbers and start the battle.

Message	From	To
Battle Invite (123)	Aaron	Britney
Battle Accept (456)	Britney	Aaron

Once numbers have been exchanged, they are combined to do a hash computation. The formula is:

SHA256("%d/%d/%0x/%d", aaronMessage, britneyMessage, localNodeNum, counter)

Nodes will compute hashes, increasing the counter, until one of the following happens:

• A counter is found, for which the hash ends in four zeros
  • Input: "123/456/4359109c/54633"
  • Hash: 7724bec8bb34ae39a85af34402f4b4a08db7a8edd6d0230f166b014cc1950000
• The counter reaches 100,000 iterations -- Nodes give up.
• The other node finds a counter better than our current best iteration (i.e., even if we find a matching hash, our counter will lose).

Once Naras find a matching counter, or give up searching, they'll message the other one letting them know of their counter. The counter is verified upon reception by the other node.

Message	From	To	Meaning
Battle Turn (432)	Britney	Aaron	(waiting for Aaron)
Battle Turn (1234)	Aaron	Britney	Britney wins: 432 < 1234

What are the next steps?

I'm sharing this project to see if there's potential in merging some form of this into the Meshtastic codebase.

• Short-term: Finalize protobufs, gather community feedback, and refine the core mechanics.
• Long-term: Expand the game features (e.g., collaborative modes, special node roles) and integrate graphics and sound.

Project status?

Currently, there's a working proof of concept. I'm at the point of getting community feedback before continuing developing this idea. The game could go in multiple different directions. I don't have experience with C++, so my code may need re-writing.

You can find the code here: https://github.com/meshtastic/firmware/compare/master...eljojo:meshtastic-firmware:nara-module

Working features:

• Battle mechanics described above using Protobufs
• Module that shows Nara status on Screen, including battle + points
• "Hello Nara" message sent to mesh on boot, this helps discover other Nara and recover points from previous battles (allows for unpersisted distributed database)

FAQ:

• Will this congest the network? The game will auto-disable on congested networks. The idea is to help density in sparse areas, not add noise in areas with good meshing. The game should auto-regulate, maybe decreasing hops or battling less often.
• Will this turn into a hashing arms race? Despite hashing being used, it's not a game of who computes the fastest. Hashes are only used to make it hard to predict winning moves. Imagine playing a game of rock-paper-scissors over instant-messaging! Devices of diverse capabilities have an equal footing, and often no one wins.
• Will my battery die when it's enabled? In my stress tests, it hasn't added noticeable battery drain to normal Heltec v3 devices. For wireless paper, it drains significantly faster due to e-ink refresh. More optimizations and real scientific testing can be done here.

Other Ideas:

• There's no concept of rankings or leveling up yet, but it'd be great to develop such mechanics.
• Website: I'd like a website similar to the online maps that show statistics about each Nara.
• Collaborative game mode: Two (or more) Naras join forces in trying to find the best hash.
• Special node mode:
  • Game node: Meant for battery-powered remote nodes. This node doesn't play itself; instead, it broadcasts challenges, where one or more nodes can compete. Ideally SPI backed.
  • Gateway node: Allows two-way sync over RF or MQTT between nodes and some central game database.
• DNA and mutation: Have ways for Nara to grow/mutate/reproduce.
• Graphics: I'd really like the game to have some cool graphics to show what's going on, and the status of your pet.
• On devices with buzzers, it should make sound during battles.

Requirements:

• CryptoEngine changes to add SHA256 hashing, platform dependent
• [Not yet implemented] Some storage space to store module settings/db of node battle status
  • If space is too limited, it may be an optional setting for nodes with an SPI attached
• Some RAM to store Nara DB of battle status
• New protobufs added
• would like to have: mobile and web versions, CLI support!