[citation needed] The game world is complex modeled, incorporating realistic effects like changing weather and seasons.

Computer controlled entities ('mobs') display complex behaviors, and animals will, for example, graze in herds or hunt in packs.

Ryzom offers a scenario editor that lets players design their own areas that can be uploaded and played on the official server.

Unlike normal planets, Atys is an enormous tree large enough to sustain an atmosphere and multiple ecosystems on its surface and within immense networks of branches and roots.

The various creatures in Ryzom have differing AI based upon their species that allows them to perform many realistic behaviors, such as migration and movement as a herd.

They have mastered the art that is a fusion of botany and genetic manipulation, and consequently they have constructed their kingdom and castles from massive trees grown for that very purpose.

[3] Interacting benevolently with all four homin cultures, but hostile towards each other, were two additional and far more advanced races: the magical Kami and the technological Karavan.

The Kami are depicted as elusive, chaotic, playful, and highly protective of Atys, while the Karavan are more secretive and have never been shown outside their environmental suits or far from their machinery.

In the game year 2481, the homin races were decimated when the hostile, insect-like Kitins were accidentally released from their home deep within Atys's root system.

Surviving refugees from all four homin cultures began working together in 2485 to rebuild a single, mixed society in relatively remote areas.

Soon came the added threat of the "Goo," a spreading infestation that renders areas uninhabitable and drives wildlife mad with rage.

New characters come from one of the four homin races, and start out as refugees, they are scattered survivors of the kitin invasion who have somehow managed to make it to an area called the Ruins of Silan.

[citation needed] This area, which is not connected to the rest of Atys, contains a variety of animals, as well as various traders and trainers, and representatives for the cultures in the game.

The first update, titled Changing Times, featured the addition of a merchants system in which players could sell their crafted items using vendors.

[citation needed] On October 3, 2006 an expansion called Ryzom Ring was released, offering players the ability to create their own content in the form of scenarios.

It provides a scenario editor where players can design content, and subsequently upload it to the game's main servers.

[8][9] On December 14, 2006 the Free Software Foundation pledged a donation of 60,000 dollars,[10] but the campaign ultimately raised €172,988 instead of the €200,000 requested.

Many of Ryzom's chat channels utilize DeepL translation to facilitate communication between players who do not share a common language.

[5] As of May 6, 2010, the entire software base, including client, server, and associated tools, was made available under the AGPL-3.0-or-later license, and current development uses a community-based open source model.

A 13GB archive containing all textures and effects, 3D models, animations, characters and clothing (but not music or sounds) was released under a CC-BY-SA-3.0 license.

[21] GameSpot also acknowledged the novel skill system and friendly community, but rated the game at 5.6 ("mediocre"), being unfinished and needlessly complex.