Valheim World Modifiers on a Dedicated Server: Every Preset, Modifier and Key

In single-player, world modifiers are a row of sliders on the world-select screen. On a dedicated server there is no such screen: the server has no menu at all, and every world modifier is a launch argument. That is where most people get stuck — the settings exist, they just live on the command line. This guide lists every preset, modifier and key with its exact server spelling, the one ordering rule that silently undoes your changes, and how to change the rules on a world you have already been playing.

The three kinds of world setting

Valheim's server takes three different arguments, and they stack:

Values are lower-case and written as one word — veryhard, not "Very Hard"; muchmore, not "Much more". Spell them exactly: a typo or a stray space is the most common reason a modifier looks like it "doesn't work".

Presets

Seven presets, straight from Iron Gate's dedicated server guide:

normal · casual · easy · hard · hardcore · immersive · hammer

• Normal is the game as designed, and what you get with no arguments at all.
• Casual and Easy take friction out: gentler combat, a kinder death penalty, fewer raids. Casual also relaxes portals so metals and ores can go through.
• Hard and Hardcore add consequence: tougher enemies and a harsher death penalty, with Hardcore at the far end of both.
• Immersive is about navigation rather than difficulty — it takes away the map and leans on travelling the world the long way.
• Hammer is building mode: no build cost and a quiet world, for a group that wants a longhouse more than a boss ladder.

A preset is only a starting point. Anything you set with -modifier or -setkey on top of it wins, as long as you get the order right.

The ordering rule that catches everyone

Iron Gate's guide puts it in one line: a modifier "if combined with a preset should be set after." The server reads the arguments left to right, and a preset resets the sliders it covers. So:

# Works: hard preset, but with raids switched off
-preset hard -modifier raids none

# Does not: the preset runs last and puts raids back
-modifier raids none -preset hard

If a modifier "isn't applying", check this before anything else.

Every modifier and its values

There is no normal value: to return one slider to normal, remove that -modifier argument.

For combat, the community wiki documents the actual numbers, which are worth knowing before you commit a group to veryhard:

The four keys

A full launch line

./valheim_server.x86_64 -nographics -batchmode \
  -name "Odin's Rest" -port 2456 -world "Midgard" -password "changeme1" \
  -public 1 -crossplay \
  -preset hard -modifier raids less -modifier portals casual -setkey playerevents

On Windows the same arguments go on the launch line of your copy of start_headless_server.bat. The rest of the line is covered in the dedicated server setup guide.

Changing modifiers on a world you already play

You do not need a new world. Modifiers are rules applied to the world when the server starts, not part of its terrain: stop the server, change the arguments, start it again, and the same world loads under the new rules. Builds, bosses and map progress are untouched.

Three things to know first:

• Back up before you experiment. Nothing about modifiers damages a world, but a hardcore death penalty can delete a character's inventory on the first mistake, and no setting brings that back. Copy the world out of worlds_local first — on 1.0 that is a folder named after the world.
• They apply to everyone. There is no per-player difficulty on a server; playerevents is the one setting that adapts to the individual.
• Resource rates are not retroactive. resources more changes what drops from now on, not what is already in chests.

Doing it without the command line

On a Connect server none of this is typed. The Server Settings tab has a Preset menu, a dropdown for each of the five modifiers, and a checkbox for each key. Save, restart when prompted, and the dashboard writes the arguments for you — preset first, modifiers after, which is the ordering rule above handled so you cannot get it wrong. Choose Normal and clear the dropdowns, and the server starts with no modifier arguments at all.

Frequently Asked Questions

Can you change world modifiers on a dedicated server?

Yes. They are launch arguments — -preset, -modifier and -setkey — rather than a menu. Change the arguments, restart the server, and the existing world loads with the new rules.

Why aren't my Valheim world modifiers working on the server?

Three usual causes: the -preset comes after your -modifier and resets it (the preset must come first); the value is misspelled or written as two words (very hard instead of veryhard); or the server was not restarted after the change.

Do world modifiers work with crossplay and console players?

Yes. Modifiers are server-side rules, so PlayStation 5, Xbox and Switch 2 players on a crossplay server play under whatever the server was started with. Nobody has to change anything on their own game.

Do I need a new world to change the difficulty?

No. Stop the server, change the modifiers, start it again. Take a backup first if you are moving to a harsher death penalty.

Can each player have their own difficulty?

No — modifiers apply to the whole world. The closest thing is -setkey playerevents, which bases raids on each player's own progress.

How do I turn raids off on a Valheim server?

Add -modifier raids none to the launch arguments (after any -preset) and restart.

How do I remove a modifier again?

Delete its argument and restart. A slider with no -modifier argument runs at whatever the preset sets, or at normal if there is no preset. If an old setting seems to linger, start the server once with -preset normal, which resets the sliders, then remove it again.

Want the sliders back? Valheim server hosting from Connect puts every preset, modifier and key on one settings page, on a 1.0 server with crossplay already on.