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

Feature	Status	Notes
Server-only install (clients need nothing, crossplay-safe)	Available (PC clients tested; console clients not yet)	No version check, no new items: vanilla and Xbox clients join as normal
Per-item settings for every fuel-burning piece	Available	Found automatically at startup, including pieces added by other mods
Always on	Available	Default for all light sources (torches, sconces, fires, hearths, braziers, lanterns, hot tubs, …). Keeps fuel full everywhere, also where nobody is nearby, so bases aren't dark when you arrive. While on, burn rate and schedule are kept but don't apply
Fuel burn rate	Implemented, awaiting in-game test	−10 to +10, 0 = vanilla, each step 10 %: −10 uses no fuel, +10 burns twice as fast
Daily on/off schedule	Available	On and off time on the in-game clock (06:00 = sunrise, 18:00 = sunset), one window per day. Equal times (default 00:00/00:00) = no schedule. Fuel is kept while a light is scheduled off. Only used when always on is off
Ignore rain	Implemented, awaiting in-game test	Off by default (lights go out in the rain as in vanilla). The server log lists which lights react to rain. See Limits
Correct burning while nobody is nearby	Implemented, awaiting in-game test	Vanilla burns all missed time at once when a player arrives, ignoring schedules. Inferno burns it on the server as time passes, following schedule and burn rate
Server ownership mode (experimental, off by default)	Implemented, awaiting in-game test	The server keeps ownership of fires, so no player's game burns their fuel or puts them out in rain: fuel only changes when the server says so. Exact burn rate and schedule. See Server ownership mode
Commands on signs, in chat and in the F5 console	Available	See Commands. Chat needs a second player online
In-game item names and word groups	Available	hot tub, standing wood torch, torches, braziers; typos get suggestions
Presets and undo	Available	preset night / eternal / vanilla in one command; undo steps back through your last 10 changes
Readable replies	Available	One message on screen, kept in Compendium → Message log; sign commands leave a short answer on the sign (formatting like <color=green> is kept)
Per-base control (nearby)	Implemented, awaiting in-game test	Change only the fires in your ward's area (or within 20 m); ward access required, like building
Config file with live reload	Available	Edit through your host's web file manager; no restart
AdminOnly permission switch	Available	Off by default: anyone may change settings. Anyone can turn it on; only admins can turn it off. Inferno never changes the server's admin list
Full audit log and error reporting	Available	Every command, every change (who, old → new) and every config-file edit goes to the BepInEx log
Safe uninstall	Implemented, awaiting in-game test	On a normal server shutdown Inferno switches scheduled-off lights back on before the world is saved; fuel stays as it is
Optional PC client mod: in-game settings menu	Implemented, awaiting in-game test	Same DLL on a PC client + ConfigurationManager (F1). Shows and edits the server's settings live; read-only for non-admins while AdminOnly is on. See Client mod
Per-item smoke toggle	Implemented, awaiting in-game test	Removes smoke for players who have the client mod; everyone else sees vanilla smoke
No rain flicker (client mod)	Implemented, awaiting in-game test	With IgnoreRain on, players with the client mod never have their lights put out by rain

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:

Where	How	Works when	Reply
Chat	!fires <command>	At least one other player is online. Valheim sends chat directly to other players, so a lone player's chat never reaches the server	On screen, top left
Sign	Write !fires <command> on any sign	Always, including alone and on Xbox. Signs hold 50 characters	On screen, and a short answer replaces the command on the sign
F5 console	listkeys fires <command>	Always. Needs the -console launch option (Steam: Properties → Launch options). Not available on Xbox	In the console

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.

Command	Example
help [items|presets|admin]	!fires help, !fires help presets
status	!fires status (is Inferno running? versions, counts, in-game time)
list [all|lights|stations]	!fires list lights
show <item>	!fires show hot tub
preset eternal|night|vanilla [item]	!fires preset night (all lights: lit at night, no fuel)
undo	!fires undo (reverts your own last change)
alwayson <item> on|off	!fires alwayson lights off
smoke <item> on|off	!fires smoke lights off (client mod players only)
burnrate <item> <-10..10>	!fires burnrate all -5
schedule <item> <on HH:MM> <off HH:MM>	!fires schedule lights 18:00 06:00
schedule <item> night|day|off	!fires schedule torches night
reset <item>	!fires reset all
adminonly on|off	!fires adminonly on
hidecommands on|off	!fires hidecommands off
ignorerain on|off	!fires ignorerain on
serverownership on|off	!fires serverownership on

<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.

• 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.
• 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.

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).

Section	Setting	Default	Meaning
[General]	AdminOnly	false	Only admins may change settings
	HideCommands	true	Hide !fires chat lines from other players
	IgnoreRain	false	Relight lights put out by rain or wind
	ServerOwnership	false	Experimental: server keeps ownership of fires
[<item>]	AlwaysOn	lights true, stations false	Keep fuel full. While on, burn rate and schedule don't apply
	BurnRate	0	−10 … +10, 10 % per step
	Smoke	true	Smoke on/off (client mod players only)
	OnTimeHour, OnTimeMinute	0, 0	Hour 0–24, minute 0–60 (lights only)
	OffTimeHour, OffTimeMinute	0, 0	Same; on = off means no schedule

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.
• No rain flicker: with IgnoreRain on, this player's game never puts lights out in the rain.

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:

• Rain, wind, roofs and water are checked on players' PCs. Some lights (e.g. candles, lanterns) switch themselves off in the rain; with IgnoreRain on, Inferno switches them back on within a few seconds, but they may flicker during storms. The server can't tell rain from a player's hand, so IgnoreRain also relights lights players switched off. Lights blocked by a roof or under water stay 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

Valheim version	Inferno version	Tested in-game
1.0.17	0.1.0 – 0.2.x	Yes: local and hosted dedicated servers, vanilla PC clients (incl. two players). Crossplay with console clients: not yet
1.0.17	0.3.0	Not tested in-game (released untested; unit tests only). If you see problems, use 0.2.2 and report them

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.