Superflat World on Your Minecraft Server: Custom Layers, No Villages and No Slimes

First: it only works for a new world

level-type and generator-settings are read when the world is created. If you change the line with an existing world, the server keeps loading the usual one and it looks as if nothing happened. To start a flat world you have to let the server generate another world: with a different folder name, or by moving the current one aside (how to reset the world).

Before that, make a backup in the panel's “Backups”. The free server has no backups: there, don't delete anything, rename the folder as explained below and you'll keep the old world at hand.

Setting up a flat world in the NapNodes panel

1. Open “Settings”

   Inside your Minecraft server, “The world” section.

2. Choose the type

   In “World Type”, “Superflat”. If you want your own layers, paste the JSON from the next section into “Generator settings”, all on one line; left empty, you get the classic flat world.

3. Give it another folder

   In “World folder”, type a new name, for example “flat”. The server creates the new world there and the old one stays in “Files”, untouched: to go back to it, put its name back (by default “world”).

4. Restart and join

   Changes save automatically and apply on restart: press “Restart”. The console shows when it finishes generating; join and you should appear on grass, in a plain stretching to the horizon.

Or by hand, in server.properties

1. Stop the server

   With “Stop”. World files are changed with the server stopped.

2. Set the flat type

   In “Files”, open server.properties and make the line look like this: level-type=minecraft\:flat. The server itself writes the backslash before the colon when it saves the file; if you type it yourself, that works too. If you want custom layers, paste the JSON into the generator-settings line.

3. Move the old world aside

   Rename the world folder (the one named in level-name, “world” by default) to something like “world-old”. Since Paper 26.1, which is what we install, the Nether and the End live inside “world” (in world/dimensions) and go with it; on earlier versions, do the same with “world_nether” and “world_the_end”.

4. Start it

   With “Start”, the server generates the new world.

The classic flat world (empty generator-settings)

Without generator-settings, Minecraft does the same as the single-player superflat: one layer of bedrock, two of dirt and one of grass, in the plains biome. The ground is very low (you stand at Y -60), because the world starts at Y -64.

That flat world comes with villages and strongholds. If you want it clean for building, or with more dirt underneath, write your own layers.

Your own layers: the generator-settings JSON

In today's versions, generator-settings doesn't understand the preset code shown on the game's screen (the minecraft:bedrock,2*minecraft:dirt… one): on the server it's written in JSON. These are the pieces:

layers: the list of layers, from bottom to top. Each one has block (the block, with minecraft: in front) and height (how many blocks tall). The total can't go over 384, the world height.

biome: the biome for the whole world, for example minecraft:plains, minecraft:desert, minecraft:snowy_plains or minecraft:forest. It changes the grass colour, the weather (rain or snow) and the animals that spawn.

structure_overrides: the structures that generate. With an empty list, [], none appear (no villages or pillager outposts). Careful: if you write your own layers and leave this line out, the server tries every structure that fits the biome, not just villages and strongholds.

features: with true, the biome's decoration is added, like trees and flowers. It's false by default: plain grass.

Write it all on a single line, with straight quotes ("), and copy the examples as they are to start. A typical mistake is an extra comma at the end of the list: if the server won't start or the world doesn't come out as expected, check the error in the console and review the JSON.

level-type=minecraft\:flat
generator-settings={"layers":[{"block":"minecraft:bedrock","height":1},{"block":"minecraft:dirt","height":2},{"block":"minecraft:grass_block","height":1}],"biome":"minecraft:plains","structure_overrides":[]}

level-type=minecraft\:flat
generator-settings={"layers":[{"block":"minecraft:bedrock","height":1},{"block":"minecraft:stone","height":60},{"block":"minecraft:dirt","height":2},{"block":"minecraft:grass_block","height":1}],"biome":"minecraft:plains","structure_overrides":[]}

level-type=minecraft\:flat
generator-settings={"layers":[{"block":"minecraft:bedrock","height":1},{"block":"minecraft:dirt","height":2},{"block":"minecraft:grass_block","height":1}],"biome":"minecraft:forest","features":true}

Monsters and slimes on a flat world

A flat world has monsters at night, like any world, plus slimes day and night: slimes spawn in certain chunks below Y 40, and the classic flat world's ground is at Y -60. That's why a freshly created flat world fills up with slimes.

If you want a peaceful world for building, with the server running type gamerule spawn_monsters false in the console: no monster spawns at all, slimes included, and animals carry on. Since Minecraft 1.21.9 this is no longer set in server.properties (spawn-monsters stopped being read); it's a game rule and is saved with the world (the other rules).

Another option is peaceful difficulty (difficulty peaceful), but it also removes hunger and monster damage across the whole server. For a creative building world, you'd usually also use gamemode creative Name for each player or, for anyone joining for the first time, gamemode=creative in server.properties.

The other world types

level-type also accepts minecraft\:normal (the usual one), minecraft\:large_biomes (the same biomes, much bigger; for exploring on horseback or by boat), minecraft\:amplified (towering mountains and dizzying overhangs) and minecraft\:single_biome_surface (the whole world in one biome, whichever you set in generator-settings). In the panel they're “Normal”, “Large Biomes”, “AMPLIFIED” and “Single Biome”. Like superflat, only when creating a new world.

Amplified is beautiful but heavy: generating new terrain uses quite a bit more CPU and somewhat more RAM than default, and you notice it as stutter while exploring. If you choose it, pregenerate the world with Chunky before people join, and don't run tight on RAM.

With level-seed you choose the seed for the default, large biomes and amplified types. On a flat world it hardly matters: the terrain is the same with any seed.

A flat world and a normal one on the same server

server.properties rules the main world. If you want a flat world for building and your usual survival at the same time, you need a worlds plugin like Multiverse, which creates extra worlds (flat ones too) and lets you move between them with a command or a portal: the guide to multiple worlds with Multiverse covers it. That way you don't have to touch the main world.

Frequently asked questions