Seasonal SLS Bridge 1.5.1

Seasonal SLS Bridge connects StarLevelSystem with your choice of Seasonality (RustyMods), Seasons (shudnal), or ValheimSeasons (Morgnar) to give Valheim's creatures seasonal combat traits and optional visual variants.

The goal is simple: make the world feel more alive and less predictable without changing StarLevelSystem itself, replacing modifier names, or taking control away from the active season provider.

Community & support

For mod questions, bug reports, ideas, texture contributions or general discussion, join the community Discord:

https://discord.gg/kN3cqHqWYA

Version 1.5.1 — documentation correction

This release removes internal update and test documents from the public package and corrects the README links. Gameplay, DLL, textures, icons, and configuration remain unchanged from 1.5.0.

New in 1.5.0 (also included in 1.5.1)

Choose one season provider: RustyMods Seasonality, shudnal Seasons, or Morgnar ValheimSeasons. They are optional alternatives, not three required dependencies. Install exactly one season mod separately; the mod manager no longer installs Seasonality automatically for this bridge.

• New General.SeasonProvider setting: Auto, Seasonality, Seasons, ValheimSeasons, or Disabled.
• Auto chooses Seasonality first, then Seasons, then ValheimSeasons if more than one is installed; using just one provider is strongly recommended.
• Reads each provider's effective season, including server overrides where supported. Local visual previews do not determine creature birth seasons.
• Keeps the creature's saved birth season and existing modifiers. No rerolls or retroactive changes when switching providers.
• Re-enables the optional visual system with Seasonality 3.8.4 after inspection, and adds coordination for Seasons material changes. Actual in-game verification is still pending.
• Updates compatibility checks for Valheim 1.0.17 and StarLevelSystem 1.25.1 and adjusts creature hover-name presentation for SLS changes.
• No changes to existing seasonal chances, ecology, modifier priorities, icons, creature texture content, or gameplay authority.

Compatibility status: Seasonality 3.8.4, Seasons 1.10.5, ValheimSeasons 1.2.0 and SLS 1.25.1 were checked against their DLL APIs. Complete in-game, multiplayer and visual verification is still pending. Newer versions (including SLS 1.26.0) are not explicitly verified.

Historical note: 1.4.7 was documentation-only; seasonal hover icons were introduced publicly in 1.4.8. See the Changelog for previous releases.

Visual System

The visual system complements the installed season provider instead of replacing it. It only applies supported local creature material overrides while preserving safe handoff when materials are controlled by other mods.

Current artwork status: fully finished public custom textures are currently included for the Troll, the Greydwarf family and Skeletons.
The broader visual framework and creature catalog are already prepared for additional families, which will continue to be added gradually.

When a supported creature has a matching modifier, Seasonal SLS Bridge can apply a local visual variant for that creature.

Examples include:

• Frost — winter / cold appearance
• Fire — heated or volcanic appearance
• FireNova — more unstable fire appearance
• Poison — toxic / overgrown appearance
• PoisonNova — unstable toxic appearance
• Lightning — storm-charged appearance
• ElementalChaos — unstable arcane appearance
• Big — winter heavy / imposing appearance where supported
• SoulEater — dark generic appearance
• Brutal — aggressive generic appearance

Unedited or unsupported properties are left alone so the active season mod can continue handling its normal seasonal visuals.

BalrondHumanoidRandomizer variants

For supported Skeleton and Draugr variants created by BalrondHumanoidRandomizer, the bridge resolves the randomized prefab back to its catalogued base creature and reuses that base creature's existing texture set.

This avoids maintaining duplicate textures for every randomized variant and does not cause intentionally excluded base prefabs to be added back into the visual catalog.

Version 1.4.6 also improves material-property handling: unrelated property blocks no longer block supported texture maps, failed first applications can be retried, and visual warnings include the affected prefab name for easier diagnosis.

Visual priority

If a creature qualifies for more than one supported visual, the bridge uses a fixed priority:

1. Elemental modifiers, with seasonal primary elements taking priority
2. SoulEater
3. Brutal
4. Big

This order is unchanged in 1.4.6. Big can now use a supported visual throughout the year instead of depending on a specific season.

This keeps the result predictable and avoids multiple systems trying to overwrite the same material.

Elemental visual fallback

Elemental modifiers applied directly by StarLevelSystem can still use the matching visual even if the creature has no recorded birth season.

For visual selection only:

• Frost falls back to winter
• Fire, Lightning and FireNova fall back to summer
• Poison, ElementalChaos and PoisonNova fall back to spring
• Supported autumn variants can act as an out-of-season fallback when appropriate
• Big can use its supported visual in any season

These fallbacks are visual only. They do not write a birth season, change titles, reroll modifiers or alter gameplay state.

Features

Every eligible new creature stores its birth season.

Season, birth biome and natural affinity determine the seasonal modifier profile.

With the default 100% gate and EnsureSeasonalModifier enabled, an otherwise empty valid roll can use a Minor seasonal fallback:

• Winter: Big
• Spring: Fast
• Summer: ResistFire
• Autumn: Alert

StarLevelSystem must still accept the selected modifier.

Winter — Vetrbarn

Cold-oriented traits are favored:

• Frost
• ResistFrost
• Big
• StaminaDrain
• ResistPierce
• ResistSlash
• ResistBlunt
• EitrDrain

Spring — Várbarn

Spring favors poison, adaptation and unusual mutations:

• Poison
• ElementalChaos
• PoisonNova
• ResistPoison
• Fast
• Evolving
• Splitter

Summer — Sumarbarn

Summer favors heat and aggressive elemental effects:

• Fire
• FireNova
• ResistFire
• Lightning
• Fast
• Brutal
• Big

Autumn — Haustbarn

Autumn favors lightning, poison and spiritual effects:

• Lightning
• Poison
• ElementalChaos
• SoulEater
• ResistSpirit
• Alert
• ResistPoison
• Big

The exact result is weighted, so not every creature receives the same modifier.

Seasonal Creature Names

Eligible new creatures retain their birth-season title independently of the modifier result:

• Esqueleto Vetrbarn
• Greydwarf Várbarn
• Draugr Sumarbarn
• Greydwarf Haustbarn

The bridge does not rewrite StarLevelSystem's modifier names.

The seasonal title is added separately to the creature's hover name.

Seasonal hover icons

Version 1.4.8 adds a local seasonal icon next to the creature hover name for:

• Winter
• Spring
• Summer
• Autumn

The icon and the textual seasonal title are controlled independently.

• Titles.ShowSeasonTitle — shows or hides Vetrbarn, Várbarn, Sumarbarn and Haustbarn.
• Titles.ShowSeasonIcon — enables or disables the seasonal icon.
• Titles.SeasonIconSize — controls local icon size.
• Titles.SeasonIconSpacing — controls spacing between the icon and hover-name text.

This allows, for example, an icon-only seasonal identity without the textual suffix.

The seasonal icon assets are RGBA PNG files at 128×128. The icon layer is local and cosmetic only: it does not write additional ZDO state, alter StarLevelSystem modifiers or change network authority.

Screenshots

The Troll screenshots below remain the current public showcase. Version 1.4.1 also includes completed custom textures for the Greydwarf family and Skeletons.

Fire — Sumarbarn

SoulEater

Poison — Várbarn

Elemental Chaos

Lightning — Haustbarn

Frost — Vetrbarn

Choosing a season provider

Install one of the following mods alongside StarLevelSystem:

Optional season provider	Provider version inspected	What to select
Seasonality (RustyMods)	3.8.4	Seasonality
Seasons (shudnal)	1.10.5	Seasons
ValheimSeasons (Morgnar)	1.2.0	ValheimSeasons

The season mods are not bundled or automatically installed with Seasonal SLS Bridge. If none is present, the bridge does not assign new seasonal modifiers or invent a season. The provider's own server/client installation requirements still apply; use the same season mod and configuration required by its author across your multiplayer session.

Do not run two season/world-overhaul providers together just to make the bridge recognize them. Auto selects only one, but this does not prevent the season mods themselves from conflicting with one another.

Configuration

Configuration file:

BepInEx/config/TheLionCid.SeasonalSLSBridge.cfg

Main settings:

Setting	Default	Description
General.SeasonProvider	Auto	Auto, Seasonality, Seasons, ValheimSeasons, or Disabled. Only one provider is used.
SeasonalRollChance	100	Percentage chance for a spawned creature to receive a seasonal modifier.
DelaySeconds	0.75	Delay before the seasonal modifier is applied after spawning.
IncludeTamed	false	Whether tamed creatures can receive seasonal modifiers.
LogAppliedModifiers	true	Logs successful seasonal applications.
EnsureSeasonalModifier	true	Fills empty valid rolls with the seasonal Minor fallback.
Visuals.Enabled	true	Enables or disables the local visual system.
Visuals.TextureFilter	Point	Texture filtering mode. Point preserves vanilla pixel detail; Bilinear/Trilinear can be used for HD packs.
Titles.ShowSeasonTitle	true	Shows or hides the seasonal text suffix such as Vetrbarn or Haustbarn.
Titles.ShowSeasonIcon	true	Shows or hides the local seasonal icon next to the hover name.
Titles.SeasonIconSize	Configurable	Controls the local seasonal icon size.
Titles.SeasonIconSpacing	Configurable	Controls spacing between the icon and hover-name text.

Existing configuration can be kept when updating. New settings are added automatically.

Custom textures

The visual pack is intentionally lightweight and editable.

Personal PNG edits are preserved by the texture preparation workflow, making it possible to build custom or HD visual packs without changing the gameplay logic of the bridge.

The compact package includes the required texture bases and Preparar-Texturas.ps1 to recreate the editable texture tree.

Requirements

Required dependencies (installed automatically through the Thunderstore dependency list):

• BepInExPack Valheim
• Jötunn
• YamlDotNet
• StarLevelSystem 1.25.1 or newer (1.25.1 is the reference inspected for this release; newer versions are not automatically verified)

Additionally, manually install one of the optional season providers listed above to enable new seasonal births. No season provider is a hard dependency in manifest.json.

Explicitly verified StarLevelSystem versions:

• 1.14.0.0
• 1.15.0.0
• 1.16.0.0
• 1.17.0.0
• 1.18.0.0
• 1.18.1
• 1.18.2
• 1.25.1 (API inspection for bridge 1.5.0)

1.25.1 is the most recently inspected SLS API for 1.5.0/1.5.1. Historical versions through 1.18.2 were verified for earlier bridge releases. This does not imply that every intervening release was individually tested.

Newer versions may continue working when the validated public API contract remains compatible. In that case, Seasonal SLS Bridge emits a single startup warning and continues normally.

If the required API contract is actually incompatible or missing, the StarLevelSystem integration is disabled safely and a compatibility warning is reported.

Installation

Thunderstore

Install Seasonal SLS Bridge and its required dependencies through your mod manager, then manually choose and install one of the three supported season providers. Seasonality is no longer an automatic dependency.

For the best multiplayer experience, use the same mod version and visual files on the server and clients.

Manual installation

1. Install the required dependencies and exactly one season provider.
2. Place SeasonalSLSBridge.dll in:

BepInEx/plugins/SeasonalSLSBridge/

1. Place the SeasonalTextures folder alongside the DLL.
2. If using the compact texture package, run Preparar-Texturas.ps1 to generate the editable visual variants.
3. Remove the old experimental TextureTest add-on if it is still installed.
4. Launch Valheim.

Existing creatures are not rerolled when updating.

To select a provider, see Choosing a season provider and Configuration above. For release history, see the Changelog.

Only the appropriate server authority applies gameplay changes. Players, bosses, traders and, by default, tamed creatures remain excluded from seasonal modifier application.

Compatibility and design

Seasonal SLS Bridge is intentionally a bridge between existing mods.

It does not:

• modify StarLevelSystem's internal modifier definitions;
• replace StarLevelSystem modifier names;
• edit creature stats directly;
• change spawn rates;
• change loot;
• require manual editing of StarLevelSystem configuration;
• alter the selected season provider's calendar;
• write network gameplay state just to display a visual variant;
• write ZDO or StarLevelSystem state just to display a seasonal hover icon.

The visual system is local and cosmetic. If a supported texture cannot be loaded, gameplay should continue with the normal creature appearance.

Stability

Seasonal SLS Bridge validates the public StarLevelSystem API it actually needs before enabling the integration.

The bridge 1.5.0/1.5.1 was inspected against the StarLevelSystem 1.25.1 API. In-game functional testing has not yet been documented. Newer builds such as 1.26.0 must not be treated as verified until tested.

For future versions:

• if the required public API contract remains compatible, the bridge binds the validated functions through delegates, emits one startup warning for the unverified newer version, and continues;
• if required functions are missing or incompatible, the StarLevelSystem integration is disabled safely and the problem is reported.

The bridge does not attempt unsafe internal modifications just to force compatibility. A creature's stored seasonal identity remains independent from modifier-application success.

Support, feedback and contributions

The community Discord is linked near the top of this README. Contributions and feedback are welcome, especially from experienced Valheim/BepInEx modders and texture artists.

AI-assisted development

A significant part of this mod's development, including code generation, debugging, compilation assistance, testing and troubleshooting, was done with the help of AI.

The author, TheLionCid, is not an experienced Valheim mod developer and is publishing this project openly so that more experienced modders can review it, identify problems and help improve it.

Feedback, bug reports and code improvements are welcome.

Permissions

You may adapt or modify this project for your own use, provided that you respect the licenses and credits of this project and its dependencies.

Do not redistribute the work of other authors as your own.

Credits

• TheLionCid — Seasonal SLS Bridge
• MidnightMods — StarLevelSystem
• RustyMods — Seasonality
• shudnal — Seasons
• Morgnar — ValheimSeasons
• ValheimModding — Jötunn and YamlDotNet
• BepInEx / Valheim modding community — modding framework and ecosystem

Disclaimer

This is an independent compatibility bridge. It is not an official component of StarLevelSystem, Seasonality, Seasons, or ValheimSeasons.

Updates to Valheim, StarLevelSystem or any season provider may require a bridge update.