A screenshot of the main screen in Shadow of Yserbius. The volcano billows smoke in the background, while in the foreground the Tavern is full of other players.

MedievaLands is a remake of The Shadow of Yserbius: an old school multiplayer dungeon crawler with grid-based movement, turn-based combat, and many puzzles and quests to solve in an expansive dungeon that goes deep into the earth and into the timeless beyond. Monsters have awoken in the dungeon of Yserbius and now plague the island of Twinion. Will you rise to the challenge?

Download and play now!

Recent News

Rescaling critical hits and bug fixes

By ZaneDubya on Sept 15, 2020

Hail friends! I'd like to share a change to the critical hit mechanics, a name change to the Paralyze debuff, and some other bug fixes that have been added to the game in the past week. Let's get into it!

First off, a big change: the critical hit damage mechanic for physical attacks has been rescaled. In the original game, critical hit damage could do up to 800 percent of your base dexterity damage. I had previously reduced this to 500 percent in the release of Yserbius on MedievaLands, and now I am reducing it further. The issue posed by critical hits is that they are incredibly spikey: even at 500 percent, damage done by players and monsters could easily exceed the total hit points of a stack of monsters or a player.

The new critical hit rescale has reduced critical hits to 150% of the maximum base damage. The goal of this change is to make combat depend more on your use of spells and skills, and less on a chance of landing a critical hit in before your enemies do. I've heard of encouraging comments from players who have already been testing the new critical hit function, and I look forward to hearing from you as well!

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In the Tavern, players discuss a Quest that requires the collection of playing cards.

Exchange clues and gather a party in the Tavern.

A party of four adventurers takes on five groups of goblins. Players discuss their strategy for taking on these foes.

Defeat Monsters and grow in power.

A player explores their 20 slot bag using the new-to-MedievaLands inventory interface.

New features include health bars and item tooltips.

A party of adventurers discovers the Healing Fountain in the Basement map. The automap interfce is shown on the right-hand side of the screen.

Explore, quest, and solve the mystery of Yserbius!


Download and Play

MedievaLands is free to play! Download the client for Windows and MacOS here:

The game 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 checks for updates and automatically patches itself.

If you are running an old version of Windows and see a popup about a missing .NET Framework installation, please download and install the .NET Framework 4.6.2 from Microsoft.

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

Development Information

A character portrait representing the developer, Zane.

Hi, this is Zane! I am the developer of MedievaLands. If you see me in the game (my handle is ZaneDubya), please say hello!

I am a huge fan of the original games, which were created by Ybarra Productions for The Sierra Network (later renamed 'The ImagiNation Network)'. Like so many, I enjoyed the dungeon that seemed to go on forever, and fell in love with the welcoming Yserbius community. It was one of the first online 'third spaces' - a home away from home. MedievaLands, which went live on March 29, 2019, is my remake of these favorite games from my childhood.

The MedievaLands game engine is written in C#, with the server running on .NET Core 2.1 LTS on Linux, and the client running on the FNA Framework on Windows and Mac. The total server/client codebase is approximately 126,500 lines of code. I developed MedievaLands over the course of eight months in 2018-2019, and first released the remake of Shadow of Yserbius on March 29, 2019. Adding support for Twinion took another seven months, and the Twinion Open Beta began on March 6, 2020. Including time spent writing framework code not specific to MedievaLands and time spent deciphering the Yserbius data formats and game mechanics, I estimate that I have spent 3,000 hours on the MedievaLands project.

My hope is that MedievaLands will be a fun adventure for new players and a welcome respite for returning players. You can always come home, although you may need to rebuild that home from scratch.

Credits (Yserbius)

The original Yserbius game was developed by Ybarra Productions, and was available on The Sierra Network between 1991-1996. I would be remiss if I did not mention the original development team of Yserbius - we should recognize their excellent work.

IMPORTANT! The people listed below have not participated in building MedievaLands, nor have they endorsed this project in any way.

Shadow of Yserbius 1.0
Designed by Ybarra Productions, Inc:
Scot Amos Wendy Barlow Fred Butts
Karl Buiter Sharon Chercowy Mark Dickenson
M.S. Dunhour Roy Eltham Botu Green
Aubrey Hodges Paul Lavelle Russell Lieblich
Mike McAulay Leonard Micko John Miles
Michael Moore Andy Riedel Donna Taylor
Andrew Townsley Joe Ybarra
Special Thanks to Ken Williams and all our
friends at Sierra On-line and TSN

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