Valheim 1.0 Mod Compatibility: Which Mods Still Work, Which Are Dead, and How to Fix a Broken Mod Stack

If you launched Valheim on September 9 and your modded save greeted you with a black screen, an infinite loading bar, or a wall of red text, you are not doing anything wrong. The Deep North update was the single largest change to Valheim's internal API since the game entered Early Access in 2021 — and unlike every previous major patch, 1.0 shipped with no public test branch. There was no window for mod authors to prepare. Everyone found out at the same moment.

The result is the most complete mod breakage event in the game's history. Not "a few mods need updating" — nearly every BepInEx plugin in circulation threw errors on first load, because the vanilla code they hooked into no longer exists in the same shape.

I have spent the days since launch working through this on a 19-mod stack, and I want to be upfront about what I found: about a third of my mods came back within 48 hours, another third are recoverable with forks or replacements, and the rest are genuinely dead. This guide is the map.

PC PS5 Xbox Switch

TL;DR: There are two completely separate reasons your mods broke, and they need different fixes. (1) Plugin code targeting pre-1.0 APIs now throws NullReferenceException — fixable as authors ship rebuilds. (2) Turning on crossplay swaps Valheim's networking layer to PlayFab and disables BepInEx entirely — not fixable, and not a bug. If your group spans PC and console, you must choose one or the other. There is no middle ground.

Why Every Mod Broke at the Same Time

It is worth understanding what actually happened, because it changes which fixes are worth waiting for.

Valheim mods do not run alongside the game. They run inside it. The overwhelming majority are BepInEx plugins — small compiled assemblies that use HarmonyX to patch specific methods in Valheim's own code at runtime. A mod that adds a new build piece does not ship its own inventory UI; it detours into Iron Gate's existing UI methods and alters what they do.

That architecture is efficient, and it is also extremely brittle. Every plugin is coupled to a signature — a method name, a parameter list, a field that is expected to exist. 1.0 rewrote large parts of that surface: the item database, the ZNetScene prefab registry, the skill system, and the build-piece category definitions all changed shape. A plugin that calls into ObjectDB or ZNetScene with pre-1.0 assumptions does not degrade gracefully. It throws.

Normally this is survivable, because mod authors get early access. Iron Gate has historically run public test branches before large patches, letting the modding community stabilise the ecosystem before the update reaches players. 1.0 did not get that. The patch went from internal build to worldwide release with no public beta, which means the entire modding community started work on September 9 alongside you.

So when you read that a mod "doesn't work," the accurate statement is usually: it has not been rebuilt yet. That distinction matters, because it tells you whether to wait or to move on.

The Crossplay Fork: Why You Cannot Have Mods and Console Players

This is the part that catches people out, and no amount of mod-updating will fix it.

Valheim's crossplay feature does not translate between two networking implementations — it replaces one. When a server starts with the -crossplay flag, the game abandons Steam's networking stack entirely and hands all traffic to PlayFab, Microsoft's backend service. Steam networking is not a layer sitting on top; it is swapped out at runtime.

BepInEx, and therefore every mod built on it, is loaded through Steam's networking path. On a crossplay server that path does not exist. A crossplay server is, by definition, a vanilla server.

The practical consequence is that "mods or crossplay" is a binary decision your whole group has to make together:

Your group	Crossplay setting	Mods	Trade-off
Everyone on Steam, you want mods	OFF	YES	Nothing lost — Steam networking is the default
Mixed PC + console group	ON	NO	Mods are disabled for everyone, including PC players
Mixed group, mods are non-negotiable	OFF	YES	Console players cannot join at all

Iron Gate has been clear that this is architectural rather than a policy choice. The studio confirmed at launch that there is no official mod support, no console mods, and no Steam Workshop integration for 1.0. There is no roadmap item for reconciling crossplay with the plugin loader.

If your server was set up for crossplay during Early Access and you have been running mods on it successfully, be aware that what changed is not the flag — it is that pre-1.0 builds tolerated the combination in ways the 1.0 build does not. The clean fix is to drop crossplay if everyone in your group is on PC.

Step 1: Find Out Which Mod Actually Broke

Do not start by disabling everything and adding mods back one at a time. That works, but on a 15-20 mod stack it costs you four to five full restart cycles and a lot of patience. BepInEx already wrote the answer down for you.

Open the file:

BepInEx/LogOutput.log

BepInEx writes a complete load trace every time the game starts. Scroll to the first NullReferenceException. It will be followed by a stack trace — a list of file-and-method frames. Read down that list until you find the first frame that does not start with UnityEngine and does not belong to a Valheim namespace such as ObjectDB, ZNetScene, Player, or ZDO.

That name is your culprit. Plugin code frames carry the plugin's own assembly name, so a line reading something like AzuExtendedPlayerInventory.Patches.Player_Update_Patch tells you exactly which mod threw.

One important caveat from my own troubleshooting: if Jotunn is in your stack, it is almost always innocent. Jotunn is the shared library that most complex mods depend on — the log will show many failures passing through Jotunn's frames because it is the intermediary, not because it is the fault. Fix Jotunn first (see the next section), because a stale Jotunn will produce a cascade of errors that looks like ten broken mods but is actually one.

If the log gives you several candidates, then bisect — but bisect the suspects, not the whole stack.

Step 2: The Recovery Sequence That Actually Works

Once you know what broke, work in this order. Skipping steps is what turns a twenty-minute fix into an evening.

1. Back up your world first. Copy the entire worlds_local folder somewhere outside the game directory. A mod that fails mid-save can leave a world file in a state the vanilla game will not load. This is the one step you cannot undo.
2. Pin your mod versions. If you use a mod manager, export or screenshot your current mod list with version numbers before changing anything. When you start swapping in forks, you will lose track of what you had.
3. Update BepInEx and Jotunn before anything else. These are the foundation. A rebuilt plugin on a stale loader will still fail.
4. Remove every mod from BepInEx/plugins/ — move the files out rather than deleting them, so you can restore your pinned set.
5. Confirm a clean vanilla start. Launch the game and load your world with zero mods. If it still crashes, the problem is the world or the install, not a mod, and you should fix that before going further.
6. Add mods back one at a time, restarting between each. Slow, but it produces a definitive answer. Where a 1.0-compatible rebuild or fork exists, use that instead of the original.
7. Check Thunderstore for a rebuild before reporting a bug. A large share of "broken" mods have a maintained replacement that is a search away.

I want to flag step 5 specifically, because it is the step people skip and then spend hours debugging a mod that was never the problem. After a patch this size, an updated client talking to an unupdated mod is only one possible failure mode; a half-migrated world save is another.

What Has Already Been Fixed (Updated September 11, 2026)

The recovery is genuinely further along than the volume of forum complaints suggests. The key infrastructure pieces landed within a day of launch.

Jotunn, the shared library that roughly 5,500 published mods depend on, shipped a 1.0 compatibility fix on launch day itself — September 9, 2026. The changelog for version 2.30.0 states that it "updated the majority of systems for Valheim 1.0.7." I would read "the majority" literally: the core systems are back, and one known gap is that build-piece categories have not been updated yet, which affects mods that add craftable items to specific build tabs.

BepInExPack Valheim, the loader itself, was updated within two days of launch. If you have not refreshed it, do that first — everything else depends on it.

Thunderstore's "Deep North Update" category has become the de facto compatibility index. As of September 11 it lists 291 mods carrying the tag, with new or revised uploads appearing throughout the day. That number is the most useful single signal in the ecosystem right now: a mod appearing in that category has a maintainer who has actually rebuilt against 1.0.

The most prolific maintainer by a wide margin is shudnal, who accounts for 13 of the top 20 most-downloaded entries in the category. The current download leaders give a good picture of what the community is rebuilding first — quality-of-life and storage mods, not total conversions:

Mod	Approx. downloads	What it does
ConfigurationManager	339K	In-game config UI for every other mod — the first thing worth reinstalling
MyLittleUI	258K	Compact HUD overhaul
HipLantern	173K	Equip a lantern to your belt slot
ExtraSlotsCustomSlots	141K	Extra inventory slot rows, customised per slot type
LongshipUpgrades	137K	Upgradeable longship tiers — thematic for the Deep North

You will also see a naming pattern worth recognising: several authors have published explicitly-named 1.0 forks rather than updating the original page. SkillInjector1point0fork and TeleportEverything1point0fork are exactly what they look like — community rebuilds of abandoned mods, published under new listings because the original author is unreachable or inactive.

The Deprecated Graveyard: Mods That Are Not Coming Back

Some of the most popular Valheim mods of the last five years were already retired before 1.0 arrived. The update did not kill them; it just made their absence unavoidable for anyone who had them installed and had not noticed.

Dead mod	Last updated	Use this instead
EquipmentAndQuickSlots (RandyKnapp)	October 2024	AzuExtendedPlayerInventory (approx. 1.3M downloads) or ExtraSlots — pick one, never both
Auga (UI overhaul)	November 2023	No true drop-in. AugaLite is a maintained subset covering roughly 5% of the original
Build_Camera (original)	September 2021	Build Camera (Custom Hammers Edition)
Better Networking (CW_Jesse)	November 2023	Check for community forks — the original is not coming back

On the inventory mods specifically: EquipmentAndQuickSlots, AzuExtendedPlayerInventory, and ExtraSlots all patch the same underlying inventory container methods. Running two of them together does not give you double the slots — it gives you corrupted slot references and items that disappear on reload. Choose one and remove the other completely, including its config file.

A Note on ValheimPlus

ValheimPlus deserves its own paragraph because it is the single most-installed retired mod in the game, and its status is widely misunderstood.

The original project was discontinued in December 2022. When people say "ValheimPlus works," they almost always mean Grantapher's fork, which has been the only maintained lineage since. That fork was last updated in February 2026 — before 1.0 — and is published under the telling name ValheimPlus_Grantapher_Temporary, which the maintainer describes as a stopgap rather than a continuation.

Given that V+ hooks into a very broad surface of vanilla behaviour, I would not expect a prompt 1.0 rebuild. If V+ is central to how your server plays, ValheimEnhanced is the more actively maintained alternative and is worth evaluating before you wait indefinitely on a fork that describes itself as temporary.

The Rollback Escape Hatch

If your world depends on a mod that is not coming back, and you would rather freeze your game than migrate, Steam still has the old builds.

Open Valheim in your Steam library, right-click for Properties, go to the Betas tab, and select a previous branch from the dropdown. No access code is required.

Beta branch	Rolls back to
default_pre1_0	The last build before the Deep North update
default_preal	The build before the Ashlands update
default_prebw	The build before the Bog Witch update
default_preml	The build before the Mistlands update

Two things to know before you do this. First, rollback is a group decision. A client on default_pre1_0 cannot connect to a server running 1.0, and vice versa — you will get a version mismatch error. Everyone has to move together. Second, rolling back means giving up the Deep North content entirely, including the 50+ new achievements that 1.0 introduced from a standing start of zero.

For most people the rollback is a last resort, not a first move. It is the right answer if you run a long-running community server that a specific retired mod depends on, and the wrong answer if you are simply waiting a week for a rebuild.

Mods Worth Rebuilding Your Stack Around

If you are starting fresh rather than repairing, these are the ones I would prioritise — they are actively maintained, they cover ground the vanilla 1.0 build still does not, and they are the likeliest to survive the next patch cycle.

PlantEverything (Advize) removes the single most-annoying restriction in Valheim base building by letting you plant berry bushes and mushrooms anywhere, not just in their native biome. AzuCraftyBoxes pulls crafting ingredients from nearby chests, which quietly eliminates most of the running back and forth that eats a building session. EpicLoot (RandyKnapp, requires Jotunn) adds a Diablo-style affix system to gear, and Jewelcrafting by the same author extends it into socketed gems — both are large, well-maintained mods that depend on Jotunn being current, so sequence your installs accordingly.

For magic, Wizardry (Therzie) is the most complete overhaul and is far more interesting in the Deep North's frozen biomes than it was in the Meadows. Server Devcommands is effectively mandatory if you administer a server at all. And Valheim Cuisine (Xutz), while niche, is the mod I have enjoyed most since launch — it makes cooking a genuine progression system rather than a checklist.

Should You Run Modded Valheim Right Now?

My honest read, three days in: yes, if your group is all on PC — and no if you rely on crossplay.

For an all-Steam group, the ecosystem has recovered enough to be usable. The infrastructure layer is fixed, the compatibility index is real and actively maintained, and the mods most people actually run — configuration, inventory, UI, crafting conveniences — are largely back. The gap is concentrated in large overhauls and anything that touches build-piece categories, because that is the specific part of the 1.0 API Jotunn has not finished.

I would still keep one unmodded world available. Not because 1.0 is unstable, but because the next patch will break things again, and having somewhere to go while you wait is worth more than any single mod.

For crossplay groups, the calculation is different and simpler: your server is vanilla whether you like it or not. Rather than fighting it, I would treat the current build as its own thing. The Deep North content is substantial, the achievement list gives a long-term goal structure the game never had, and 1.0 shipped at $29.99 after five and a half years of Early Access at $19.99 — the base game is finally a complete purchase rather than a bet on a roadmap. Mods can come back later.

Sources

• Valheim 1.0 Deep North launch coverage — Iron Gate Studio, confirms the September 9, 2026 release, the absence of a public test branch, and the studio's position on official mod support, console mods, and Steam Workshop.
• Jotunn on Thunderstore — version 2.30.0 changelog and launch-day 1.0 API compatibility commit; download and dependent-mod counts.
• Thunderstore Valheim "Deep North Update" category — the community compatibility index; 291 tagged mods with download rankings as crawled on September 11, 2026.
• BepInExPack Valheim — loader package update history following the 1.0 launch.
• ValheimPlus_Grantapher_Temporary — maintainer's own description of the fork as a stopgap, and its last update date of February 2026.
• Valheim Steam beta branches — rollback branch identifiers including default_pre1_0, default_preal, default_prebw, and default_preml.

For the launch-day version mismatch and crossplay setup problems that are not mod-related, see our Valheim 1.0 launch day fixes guide. For a full walkthrough of the new content itself, start with the Valheim 1.0 launch guide.