Inferno

Server-side control over every fire, torch and fuel-burning station in Valheim. Players install nothing, so it works with Xbox / Game Pass crossplay.

Source code, documentation and issue tracker: https://github.com/krab7191/valheim_inferno_mod

Status: beta. Every feature is unit-tested. Features marked Available have also been verified in-game on dedicated servers (local and hosted) with vanilla PC clients; the others are awaiting in-game testing (see Compatibility).

Features

Items that are not light sources (smelters, blast furnaces, ovens, …) keep vanilla behaviour until you change them. Items without fuel (e.g. the charcoal kiln) and fires with infinite fuel are not listed.

Installation (server)

With a mod manager (r2modman, Thunderstore Mod Manager, or your host's Thunderstore mod installer): install GrundleLord-Inferno. BepInExPack Valheim is installed with it.

By hand:

1. Install BepInExPack Valheim on the server (most hosts have a one-click option).
2. Copy Inferno.dll and Inferno.Core.dll (in the download's plugins folder) to the server's BepInEx/plugins/Inferno/ folder.
3. Restart the server. The log (BepInEx/LogOutput.log) shows Inferno … loaded and lists every item it found.
4. Settings are in BepInEx/config/GrundleLord.Inferno.cfg (created on first start). A fully commented sample-config.cfg comes with the download (also on GitHub).

Players don't install anything. A one-page guide for players (also console players) explains how to use Inferno with signs.

Commands

Three ways to type the same commands:

The F5 form borrows the vanilla listkeys command because Valheim only forwards built-in server commands to the server. Without Inferno it just lists world keys, so it is harmless.

<item> is the name as shown in game, e.g. hot tub, standing wood torch, campfire (case, spaces and punctuation don't matter; a name shared by several items changes all of them); a word that selects every item with it in its name, e.g. torches, braziers, fires, lanterns; or a group: all, lights, stations. Internal names like piece_bathtub work too. Typos get "did you mean" suggestions. When a word selects several items, the reply lists them.

Presets set everything in one go: eternal = always on (the default), night = lit 18:00–06:00 and never uses fuel, vanilla = plain game behaviour. They apply to all lights unless you name something (!fires preset night torches); vanilla without a name applies to everything.

Replies appear top left for a few seconds and stay in the game's message log (Compendium → Logs). A command written on a sign is replaced by a short answer, so the result stays readable until you write the next command.

Example: torches that light at dusk and never need fuel. One command: !fires preset night torches. That's the same as doing it by hand (always on overrides the schedule, so it's switched off):

!fires alwayson torches off
!fires burnrate torches -10
!fires schedule torches night

Changed your mind? !fires undo.

Only your base: nearby. Add nearby after the item to change only the fires around you (chat, F5) or around the sign, e.g. !fires preset night nearby or !fires burnrate torches nearby -5. Presets still change only lights unless you name something (!fires preset eternal smelter nearby).

• Inside a ward, "nearby" means that ward's area, and only players with access to the ward (its builder and the players they added) can change its fires: the same rule as building there.
• Without a ward it means everything within 20 m, and anyone may change it, as with building.
• With a number, e.g. nearby 2, it means exactly that many metres (1–100) around you or the sign, even inside a ward. Ward permission still applies to every fire. The number goes right after nearby, before the value: !fires burnrate torches nearby 5 -10.
• Those fires keep their own settings (saved with the fire, also after a restart); later changes to their item type don't affect them. !fires show nearby lists them; !fires reset nearby makes them follow their item type again.

Example: a clock. Place 12 torches in a circle, at least 2 m apart, each with a sign right next to it. Going clockwise from the top, write !fires schedule nearby 1 00:00 12:00 on the first sign, 01:00 13:00 on the next, and so on up to 11:00 23:00. Each torch burns for 12 hours, so the lit arc grows from the top in the morning and shrinks from the top in the afternoon: top torch lit = morning, the last lit torch is the hour; top torch dark = afternoon, the last dark torch is the hour (+12).

Always on vs. burn rate and schedule: while always on is on, burn rate and schedule have no effect. Setting a burn rate or a schedule window therefore switches always on off for those items (the reply tells you). Turning always on back on keeps your burn rate and schedule stored, so nothing is lost.

Configuration

Everything the commands change is stored in BepInEx/config/GrundleLord.Inferno.cfg, and edits to that file apply live. A fully commented sample-config.cfg comes with the download (also on GitHub).

Optional client mod (PC)

Players don't need anything. PC players may install the same Inferno files (plus ConfigurationManager, which many modded setups already have) to get:

• A settings menu: press F1, open Inferno. While connected to a server running Inferno, the menu shows the server's settings and changes apply to the whole server immediately (they are sent as normal commands, so the same permissions and logging apply). With AdminOnly on, non-admins see the settings read-only.
• Smoke toggle: items set to Smoke = off make no smoke for this player.
• Fires in rain: after !fires ignorerain on, fires burn normally in rain for this player.

On a server without Inferno, or in single-player without a world loaded, the client mod does nothing. Version mismatches between client and server are detected; the menu is then disabled with a message.

Server ownership mode (experimental)

Normally the player nearest a fire "owns" it, and their game burns its fuel and switches it off in rain; Inferno corrects from the server. With ServerOwnership on, the server keeps ownership of every eligible fire instead:

• No player's game burns the fuel, so it changes only when Inferno says so: always-on fires never drop, burn rate and schedule are exact, and there are no update collisions.
• Rain and wind can't switch these fires off.
• Adding fuel and switching on/off are handled by the server, so nothing is lost.
• Deconstructing, repairing or damaging a fire briefly hands it to that player (30 s) so the game handles it normally. The action takes about a second longer than usual; if it doesn't happen, try again.
• Side effects: no sound or flash when adding fuel or switching these fires.
• Excluded (keep normal behaviour): fires that melt Deep North snow or spread fire, and pieces with other player-run parts (smelters, containers, …). The server log lists them.
• Turning it off gives every fire back immediately; Inferno also gives them back on shutdown.

Known limits

These come from how Valheim works and apply to any server-only mod:

• Fires smoulder in the rain, and the server can't stop it. Each player's PC decides whether a fire is wet (uncovered in rain, or strong wind) and then draws it as small embers with steam: it looks out, but it keeps burning, keeps its fuel and flares up again when the rain stops. A roof over the fire (with room for the smoke) keeps it lit.
• Roofs and water are checked on players' PCs too: a fire with something solid right above it, choked by its own smoke, or under water stays out.
• Burn rate is close, not exact, while a player is nearby. That player's game burns the fuel; Inferno corrects the amount every 5 seconds. While nobody is nearby, the server burns fuel itself, exactly, following the burn rate and the schedule.
• Chat commands need a second player online (see Commands); signs and the F5 console always work. Console players whose platform privacy settings block text chat can always use signs.
• Smoke can only be removed for players who have the client mod.
• Uninstall: stop the server normally (not a forced kill), then remove the files. Fuel levels stay as they are and burn normally afterwards.

Troubleshooting

1. Write !fires status on a sign (or listkeys fires status in the F5 console). If nothing answers, Inferno isn't running on the server. The last line shows errors since start.
2. Open the server's BepInEx/LogOutput.log (most hosts show it in their file manager). Search for Inferno:
   • the startup diagnostics block lists versions, crossplay on/off, other mods, and any other mod that hooks the same game methods as Inferno (the usual cause of conflicts);
   • every command, change and reply is logged;
   • errors are logged in full the first time and summarised if they repeat. Inferno skips the failing object and keeps running.
3. Report problems on GitHub Issues and include the startup diagnostics block and the first error.

Compatibility

Inferno targets the latest stable Valheim release only. New game patches are tested as they ship; older game versions are not supported.

License

MIT © 2026 GrundleLord.