A from-scratch recreation of The Shadow of Yserbius!


This site is a dev blog for a fan-made cross-platform copy of The Shadow of Yserbius. Released in 1993, Yserbius was one of the first online graphical RPGs. Up to 60 people at a time could meet up, create adventuring parties, and delve deep into monster-filled dungeons. When you were done adventuring, you could venture off with your friends to play other games on the Imagination Network, which modestly described itself as "the friendliest place in cyberspace".

I have very fond memories of Yserbius and the Imagination Network. This is my attempt to recreate that kind of experience: the ability to create a persona, to play fun games with other people, and to be a part of a community that is welcoming and affirmative.

IMPORTANT! This is not an official release, just a closed-source hobby project. I do not have the permission of the rights holders or owners of The Shadow of Yserbius.


Platform Notes
Windows You will not be able to run this program unless you approve it by clicking 'More Info' in the Windows SmartScreen popup. For more information, please review How-to-geek's article about SmartScreen.
Mac OS If you have difficulty running this application, please review Apple's notes on running trusted software.

Application Information

When you run the program for the first time, it will copy itself to your Documents directory under /Games/CommunityKit. It does this so it can update itself in a known location.

Each time the program runs, it first checks if the program files have been updated, and then checks if any resource files must be updated. Resource files can be large (the music files are approximately 20mb), but they only need to be downloaded once.

I will do my best to make sure that the program can patch itself, but it may be necessary, during the first few months of operation, to issue 'breaking' patches, which will require you to download the client from this website again.

I'm looking forward to seeing you on-line!

Development Road Map

  • Release date: March 29, 2019.
  • Currently focusing on hypercare and stabilization after launch, expected through May 2019.
  • Other features in the works: Card and Board game frameworks, social features (bulletin boards, mail, guild management).

Programming Facts

This recreation runs on a homemade engine called "CommunityKit". CommunityKit is written in C#, with the server running on .NET Core 2.0, and the client running on the FNA Framework on Windows and Mac.

The total server/client codebase is approximately 89,600 lines of code. This code is a from-scratch recreation of Yserbius: old cheats like Vitamin F do not work, and old bugs do not exist. In return, please enjoy the new bugs I have introduced (and am rapidly hunting down!).

The CommunityKit Engine took me seven and a half months to develop. Including time spent writing framework code not specific to CommunityKit and time spent deciphering the Yserbius data formats and game mechanics, I estimate that I spent 2,500 hours on this remake.

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