Valheim 1.0 Patch Notes for Server Owners: Deep North, Save Changes, Mods, Hotfixes 1.0.10 to 1.0.14

Valheim 1.0 shipped on September 9, 2026. The patch notes are long, and most of the list (40+ weapons, 4 armour sets, 10+ creatures, 80+ build pieces, 20+ foods) is for players. This post is the other part: what changed for the person running the server, what to do in which order, and what the three hotfixes since launch fixed. If you're setting up a fresh world for a group that's coming back for the Deep North, Valheim server hosting at Host Havoc starts on the current build with crossplay ready to switch on.

What actually changed on the server side

Less than you'd expect from a 0.221 to 1.0 jump.

• No new or changed launch arguments. -crossplay, -name, -world, -password, -port and the world-modifier flags all work as before.
• The player cap is still 10. Iron Gate's 1.0 FAQ calls it "a game for 1-10 players".
• The save format is new. A world is now a folder named after the world, holding .fwl2, .db2 and .chunks files plus a cache folder, instead of the old .fwl and .db pair. An existing world is converted the first time a 1.0 server loads it. Our upload a world guide has the new folder layout and the local paths where Steam now keeps worlds.
• The engine was upgraded to a newer Unity version. That's the line that broke mods (more below).
• Version matching still applies. A client on 1.0 cannot join a server that's still on the last early access build, and vice versa.
• The price rise to $29.99 is for the game itself. It changes nothing about a rented server.

Keep your world or start over

Iron Gate's own answer: your old world gets the new content, but "biome generation will only work properly on areas that have not yet been explored", and they recommend starting from scratch.

In practice that means one question: has anyone in your group sailed to the northern edge of the map? The Deep North is always in the north. If that terrain has already been generated by someone exploring it in early access, the new biome doesn't populate there. Groups that stayed south of the Mistlands are usually fine to carry on. Groups that sailed the whole coastline should start a new seed.

Your old saves aren't touched either way. The FAQ is explicit that nothing happens to them at launch, so keeping the early access world as a backup and starting a fresh one costs nothing except a world name.

Update order for a mixed PC and console group

Update the server first, then tell players to update. A server on the old build can't take 1.0 clients, so if half your group updates through Steam overnight and the server hasn't moved, they're locked out until you restart it.

On a Host Havoc server: stop it, run Steam Update from the control panel, start it, and check the Web Console for the version line before you post the all-clear.

Hotfixes have been arriving at different speeds per platform. The September 11 hotfix reached Steam as 1.0.12 while other platforms got 1.0.10 (Xbox shows it as 1.0.11), and the Switch 2 build was late enough that Iron Gate posted an apology. The September 17 patch came with a note that it "will require a few days to get uploaded to all platforms". In both cases Iron Gate said crossplay stays working across the mismatched builds, and that has held on our servers so far. Don't assume a console player who can't connect has a version problem; check the join code first.

Back up before you change anything

The concrete reason: patch 1.0.12 fixed items losing durability and upgrade level when removed from armour stands and item stands, but only for stands nobody has been near since 1.0 launched. Iron Gate's note tells players not to remove high-level items from stands without a backup until a fuller fix ships. On a shared server, several people may have loaded that base since September 9, so the "haven't been near it" condition is hard to guarantee.

Host Havoc keeps automatic saves in worlds_local and offsite copies on top. The restore a backup guide covers the three ways to roll back, including the one-click Restore Backup icon in the panel. Take one before the update, and take one before anyone starts pulling gear off stands.

Mods

There was no public test branch for 1.0, so mod authors got the new code the same minute everyone else did. Add an engine upgrade and the result is that a BepInEx server that ran fine on September 8 usually wouldn't start on September 9. Iron Gate said in July they "cannot guarantee that any mods will be functional when 1.0 releases", and that turned out to be the case.

What to do:

1. Update the BepInEx pack itself first. The Valheim pack on Thunderstore has a 1.0 build; an old loader with new plugins fails the same way as the reverse.
2. Update Jötunn and any other shared library your mods depend on before the mods themselves.
3. Re-enable one mod per restart and read the console for the first red error, not the last.
4. Any mod without an update since September 9 is a mod to leave off.

If the server won't start at all, pull the BepInEx/plugins folder aside and boot vanilla to confirm the server is fine and it's the mod stack. On Host Havoc the panel installs BepInEx in one click from the Non Workshop Mod menu; the BepInEx install guide has the steps and the plugin folder path.

One more constraint that's new: PS5 and Switch 2 players can't install anything. Server-only mods are fine on a crossplay server. Any mod that needs a copy on each client locks console players out.

Crossplay now includes PS5 and Switch 2

The mechanism hasn't changed since Xbox crossplay arrived in 2023. The server starts with -crossplay, prints a six-digit join code in the console, and console players join with that code while Steam players can still use IP and port. What changed on September 9 is the size of the console audience.

It matters for hosting because neither PS5 nor Switch 2 can run a dedicated server. A console group that wants a world that stays up while the host is offline needs someone on PC to run one, or a hosted Valheim dedicated server. Turning crossplay on is a checkbox in the Command Line Manager; the enable crossplay guide shows where the join code appears.

Cross-save is narrower than crossplay. Per the FAQ, saves only follow you between Xbox and the Microsoft Store version on PC. A Steam, PS5 or Switch 2 character stays on the device it was made on. Characters are stored client-side, so this doesn't affect the server world; it affects who can bring an existing character to it.

Ban lists, whitelists and the new player IDs

1.0 introduced a platform-neutral player ID format (V_123456789) alongside the old Steam_123456789 style. On the launch build the banlist and whitelist only matched the new format, so any bans you'd written with Steam IDs stopped applying. Patch 1.0.12 fixed it on Steam, with other platforms following. If your server ran with a whitelist between September 9 and the hotfix, check the list still does what you expect. The add admins guide covers where the admin, ban and permitted lists live and which ID goes in each.

Devcommands on a shared world

Achievements are new in 1.0 and they change what spawn costs. Per the FAQ, using most devcommands puts a permanent flag on both the character and the world save, and there's now a confirmation prompt before you enter a cheated state. Spawned items carry the mark. A clean character who picks one up enters a temporary cheat state until they drop it. On a server, one admin spawning a stack of iron flags the world for everyone.

Patch 1.0.12 added a way back: a devcommand, written as "yesiuseddevcommandsbutiwantmyachievementsanyway", opts you into achievements regardless. 1.0.14 then fixed characters being wrongly marked as temporary cheaters from monster drops. Our console commands list still applies; the flag is the new consequence.

Hotfix log, server-relevant lines only

1.0.10 / 1.0.12, September 11. 1.0.10 went to all platforms (Deep North heavy armour repairable, Greydwarf Shaman damage, snow fixes, sounds). 1.0.12 was Steam-only at first: banlist and whitelist accept old IDs again, a crash when a player accessed an unloaded zone, the item stand durability fix with the backup warning above, the achievements opt-in command.

1.0.14, September 17. Fixed characters not saving correctly when manually pressing Save on someone else's server. Disabled biomedata caching, which could get into a state that made joining remote servers impossible. Fixed terrain modifications causing performance and portal problems in multiplayer, including terrain seams and edits being undone. Rollout to consoles takes a few days; crossplay keeps working in the meantime.

This section gets updated as patches land.

Starting a 1.0 world on Host Havoc

If you'd rather not manage the update order, backups and mod loader yourself, you can rent a Valheim server from $9.99 a month in 14 locations. New servers deploy on the current build, crossplay is a checkbox, BepInEx is a one-click install, and backups run automatically with offsite copies. Support averages under 10 minutes to first response, and the team has handled every Valheim update since 2021.