Valheim World Modifiers on a Dedicated Server

How world modifiers work on a dedicated server

World modifiers arrived with Hildir’s Request in patch 0.217.14. Patch 0.217.22 is the important one for server admins, because it made modifiers controllable on dedicated servers through startup parameters or the admin console. From that point on, the dedicated server could do the same basic job as a local world: hold a ruleset inside the world save and apply it to everyone who connects.

The useful part is understanding when each method takes effect. A console command changes the running world immediately. A startup line or host panel applies when the server loads the world. That means the live world can say one thing right now, then a restart can write a different ruleset over it before anyone logs back in.

Think of it as three routes to the same saved world, each taking effect at a different moment.

If changes seem to “disappear”, the server is rarely ignoring you. It is usually doing exactly what you told it to do on start, and that boot-time instruction is beating the live tweak you made earlier.

The startup line: where permanent modifier changes usually belong

On Windows, the file is start_headless_server.bat. On Linux, it is start_server.sh. Iron Gate recommends editing a copy, because Steam resets the original on updates. That is why people edit the file, see it work once, then lose the change later. If you still need the base server files, see our guide to setting up a Valheim dedicated server.

All of the arguments sit on the line that starts start valheim_server. Stop the server with CTRL+C in the console window, not the X. A clean stop lets the server save the world before it exits, so the next start loads the state you expect.

Each modifier needs its own -modifier argument, and each checkbox key needs its own -setkey. Do not comma-separate keys, and do not leave a space between the dash and the word. A malformed flag is simply ignored, with no error in the console, so a typo looks exactly like a setting that “does not work”.

Here is a complete example. The world parameters come first, then the preset, then the individual modifiers, then the checkbox keys. Leave out -crossplay if everyone plays on Steam.

start valheim_server -nographics -batchmode -name "Group World" -port 2456 -world "DedicatedWorld" -password "YourPass" -crossplay -preset hard -modifier raids none -modifier resources more -setkey playerevents

That line gives a hard-combat world with raids switched off, 1.5x resources and raids that follow each player’s own progress if you later turn raids back on.

The order rule is the part most guides skip. A preset is not just a label; it writes a whole bundle of modifier values, and Iron Gate’s own guide says setting a preset overwrites any modifiers set before it. So the server has to read the broad bundle first, then your per-category overrides, then the on/off keys.

If you put -preset after custom modifiers, the preset silently replaces them. That is why a line can look correct at a glance and still boot into the wrong ruleset.

What each modifier really changes

Pick these by number, not by name. “Easy” or “hard” sounds subjective; the actual values are not.

Combat

Hard and very hard also mean starred enemies show up more often. Very hard doubles enemy damage while cutting yours to 70%, so a group that is comfortable on normal will feel it at once: longer fights, more deaths and messier base defences.

Death penalty

This setting shapes how a group feels about dying more than anything else. Its trade-off is social: harsher death rules slow recovery, split groups and create more corpse runs. If the goal is to keep people together after a wipe, easing death penalty usually helps more than changing raw combat numbers.

Resources

Resources do not regenerate terrain and do not change world generation. They change drop results. Drops round up, so 1.5x on a one-item drop becomes 2, which is why “more” often feels closer to 2x in everyday play. It does not affect fish, trophies or boss drops. If your group is short on play time, more is the gentlest way to speed up progress without touching combat.

Portals

Portal rules mostly change logistics rather than raw server performance. Casual portals cut down on hauling time and failed recovery runs. Very hard portals force ships, roads and staging bases, which is great for some groups and exhausting for others.

Raids

Raids work on a timer and a dice roll. On normal, the game checks for a raid every 46 minutes with a 20% chance. Much less stretches that to every 92 minutes at 10%, less to 69 minutes at 13.33%, more shortens it to 27.6 minutes at 33.33%, and much more to 13.8 minutes at 66.67%. The chart shows how quickly that adds up.

On much more, a raid is more likely than not at every check, and the checks come more than three times as often as on normal. Set raids to none if the aim is quiet building, but remember that night spawns still happen.

Presets decoded

Start from a preset when one of these bundles is already close to the server you want. Build your own when you only want one or two changes. That avoids the common mistake of applying a preset for one useful part, then spending the rest of the day undoing the parts you did not want.

• nobuildcost: build pieces need no materials, but recipes still need discovering. It does not cover general crafting, and from 0.219.16 food placement is separate from this.
• playerevents: raids follow each player’s own boss progress instead of world boss progress, which is much friendlier for mixed-progress groups.
• passivemobs: enemies do not attack until provoked. Mobs spawned by bosses still aggro.
• nomap: no map or minimap for anyone on that world.
• fire: part of Immersive; it lets fire spread outside the Ashlands. The console key is Fire, but it is not in Iron Gate’s official startup -setkey list.

Change modifiers live from the admin console

For live changes, put admins in adminlist.txt, one case-sensitive ID per line in the format [Platform]_[User ID]. Get the ID from the server log or the in-game F2 panel. Admins add -console to Valheim’s Steam launch options, then open the console with F5.

You do not need devcommands for world modifiers on a dedicated server. In fact, ordinary cheat commands do not work on a dedicated server, which is where some “unknown command” confusion starts.

setworldpreset <preset>
setworldmodifier <modifier> <value>
setkey <key>
removekey <key>
setkey PlayerDamage 150
listkeys
resetworldkeys
setworldpreset default

These apply to the running world immediately, so they are ideal for trying a raid rate or portal rule without kicking everybody off. Use listkeys straight away to confirm the live state; on a dedicated server it prints the list, which is much better than guessing from feel alone.

The big caveat is reset behaviour. There is no single “normal” value for one category, so something like setworldmodifier portals normal is not the documented route back. Reset everything with resetworldkeys or setworldpreset default, then re-apply the settings you actually want. That works because modifiers are stored as global keys; a full reset clears the saved key set instead of trying to unset one piece in isolation.

Checkbox keys on existing worlds are safest changed with setkey and removekey, then verified with listkeys. You can also use number keys such as setkey PlayerDamage 150, where 100 is the default. For the wider admin toolset, see our guide to Valheim server settings and commands.

Rented servers: panel GUI versus console

Some hosts expose world modifiers properly in their panel, and some still leave you typing launch arguments. The panel matters because if it writes those values on every start, that panel becomes the real source of truth for permanent changes.

The trap is simple: a console change can work now, everyone logs off happy, then the next restart reloads the panel values and the server “undoes” it. Use the console for trials and mid-session tweaks. Use the panel or startup line for any change that must survive the next boot.

Changing modifiers on an existing world safely

Yes, you can change modifiers on an existing world. Back it up first. If you need a proper safety copy before you experiment, follow our guide to backing up your Valheim world.

• What changes: the world’s saved ruleset.
• What does not change: terrain does not regenerate, and boss progress stays.
• What carries over: a world uploaded from single-player keeps the modifiers it already had.

That last point catches a lot of groups. If you are moving a single-player world to your server, inspect it after first boot instead of assuming it is on defaults.

If the world has old or unknown settings, do a clean reset before fine-tuning. On a live server, use resetworldkeys or setworldpreset default. From the startup line, Iron Gate added -resetmodifiers for the same clean-up. Then apply the exact values you want and verify them. This avoids half-reset worlds where one inherited key keeps causing confusion.

The check that matters most is after the restart. If the setting was right live but wrong after boot, the problem is not the world; it is the thing writing values during startup.

Recommended setups for common groups

In every case, keep the order intact: preset first if you use one, then per-category modifiers, then keys.

Symptom, likely cause, first fix

Self-host or rent: who makes modifiers easier?

World modifiers work the same everywhere. What changes is how much of the fiddly part you handle yourself.

If you would rather click than type, the panels in the table above are the easy route, and our Valheim server hosting comparison covers how those hosts compare on price, locations and support.

Valheim server FAQ

Can you change world modifiers on an existing Valheim server?

Yes. Modifiers are part of the world save, so you can change them on an existing dedicated world through the startup line, the admin console or a host panel. The change does not regenerate terrain or erase boss progress, but it does affect everyone who joins that world.

Why did my Valheim preset reset my other modifiers?

A preset writes a full bundle of settings, not just one label. If it loads after your custom modifiers, it replaces them. Put -preset first, then your -modifier entries, then any -setkey values.

Do I need devcommands to change world modifiers on a dedicated server?

No. Dedicated-server world modifier commands are admin commands, not cheat commands, so they do not need devcommands. Make sure your ID is in adminlist.txt, use -console on the client and open F5.

What are the best world modifiers for a group with different progress?

The key setting is playerevents, because it makes raids follow each player’s own boss progress instead of the world’s overall boss kills. Many groups pair that with -modifier portals casual and -modifier resources more so travel and catch-up are easier without flattening combat.

How do I turn a world modifier back to normal?

You cannot reliably set one category back to “normal” with a single setworldmodifier command. The documented route is to reset all world keys with resetworldkeys or setworldpreset default, then re-apply the settings you still want. On startup, use a clean default base such as -preset Normal before adding custom overrides.

More Valheim server help

The host comparison, plus our other guides to running a Valheim server.