You don’t have to start over. Whether you have a singleplayer world you want to share or a server you’re moving from another host, the process is the same: replace Levyathan’s world folder with yours. The two rules that make it work are: match the Minecraft version, and take a backup first.
Understand the world folder
A Minecraft server keeps its world in a folder named, by default, world - with separate world_nether and world_the_end folders for the other dimensions. Inside world are level.dat (the world’s metadata and seed) and the region/ folder (the actual chunks). A singleplayer save (in .minecraft/saves/<name>) has the same structure, just with the Nether and End nested inside it.
Move a singleplayer world
- 1Create a Levyathan server on the SAME Minecraft version your world was last opened in. This matters - see the warning below.
- 2Find your save: .minecraft/saves/<YourWorld> (Windows: %appdata%\.minecraft\saves). Zip its contents.
- 3On Levyathan, stop the server, open the Files tab, and delete the existing world, world_nether and world_the_end folders.
- 4Upload your zip, extract it, and rename the result so the main folder is exactly world (and, if your save nested them, move DIM-1 / DIM1 out to world_nether / world_the_end - or just keep the single world folder; Paper will read nested dimensions too).
- 5Start the server and join - you should spawn in your world.
Move from another host
- 1On the old host, stop the server and download its world, world_nether and world_the_end folders (or a full file backup).
- 2On Levyathan, match the version, stop the server, and replace those same folders in the Files tab.
- 3Bring over plugin data too if you want to keep it: upload the relevant folders under plugins/ (e.g. your EssentialsX or LuckPerms data). Re-install the plugins themselves from the Plugins tab so they match your version.
- 4Start and verify.
The version rule (read this)
Minecraft upgrades a world’s data format when a newer version opens it, and that upgrade is often one-way. Loading a 1.20 world on a 1.21 server will convert it; loading a newer world on an older server simply won’t work. Always set the Levyathan server to the version your world came from, and if you do intend to upgrade, take a backup first so a bad conversion isn’t permanent. The level-name line in server.properties must also match your world folder’s name (it’s world by default).
Always back up first
Before replacing anything, create a backup from the Backups tab. If an upload goes wrong or the version conversion misbehaves, you restore in one click and try again. Migrations are low-risk when you have a snapshot to fall back to.