Bifrost Mod Kit

Bifrost mods are folders in the game's mods folder. Each one has a mod.json that lists what it adds or changes: game data rows, text, art, music or sounds. They load when the game starts. Below is what you can change, with examples from the sample mods.

Getting started What you can change Bifrost on GitHub

mods\sample-skin\mod.json

{
  "id": "sample-skin",
  "name": "Sample skin",
  "version": "1.0",
  "tables": {
    "costumeTypes": [{
      "copy": "Bear",
      "set": {
        "CostumeName": "BHSampleTealbear",
        "CostumeID": "@id",
        "CostumeIndex": "@id/OwnerHero",
        "Body1_Define": "0x1A8C82",
        "Special_Define": "0xD4A017"
      }
    }]
  },
  "strings": { "English": { "BHSample_Tealbear_DisplayName": "Tealbear" } }
}

Getting started

1
Make a folder
Next to Brawlhalla.exe, create mods\my-first-mod.
2
Add mod.json
It needs an id, a name and a version, then whatever the mod changes. The example renames a menu button.
3
Start the game
Mods load when the game starts. The Mods screen shows yours and lets you turn it off.
4
Check the report
Documents\Bifrost\bh-mods.txt says what loaded, what changed, and why anything was skipped.

mods\my-first-mod\mod.json

{
  "id": "my-first-mod",
  "name": "My first mod",
  "version": "1.0",
  "strings": {
    "English": { "UI_MainMenu_Offline": "Practice" }
  }
}

After a restart, the Offline button on the main menu says "Practice".

What you can change

Click a card for details and an example. Visual mods are fine online. Gameplay mods only work offline and in custom rooms where everyone has the same mods.

SkinsVisualRecoloured skinsCopy an existing skin and change its colours.Details

How: Copy an existing skin in costumeTypes, give it a new CostumeName, use @id for its IDs and set new colours.
In game: Character select, next to that legend's other skins. You own it right away. Mods > ADDED ITEMS has a preview.
Note: You can't pick IDs yourself. @id takes the next free one, and it comes out the same on every PC with the same mods.

sample-skin

{ "copy": "Bear", "set": {
  "CostumeName": "BHSampleTealbear",
  "CostumeID": "@id",
  "CostumeIndex": "@id/OwnerHero",
  "DisplayNameKey": "BHSample_Tealbear_DisplayName",
  "Body1_Define": "0x1A8C82" } }

SkinsVisualSkins with custom artNew art, weapons, signature effects and sounds. Added as a new skin, the original stays.Details

How: An art-only SWF loaded through assets, plus MasterFileList and BoneSources rows. palette makes colour schemes work on it, animationAliases borrows lock-in animations, soundBanks adds its sounds.
From a .bmod: Drop a community .bmod skin into the mods folder and the game converts it. It becomes a new skin instead of replacing the original.
In game: Character select, with its weapons and signatures. People who don't have the mod see the skin it was copied from.

mod.json (parts)

"assets": { "bones/Bones_MySkin.swf": "bones/Bones_MySkin.swf" },
"animationAliases": { "MySkin": "Xavier" },
"soundBanks": [ "audio/MySkin.bnk" ],
"palette": { "costume": "MySkin",
  "colours": { "3a7bd5": ["1a8c82", 0.016, -0.067, -0.02] } }

ColoursVisualColour schemesExtra colours in the colour picker.Details

How: ColorSchemeTypes rows. The in-game Colour editor can write these for you.
In game: The colour picker, for every legend. Bifrost allows up to 1024 colour schemes (the game stops at 160).
Note: The game is strict about this table. Copy a full existing row and edit that.

sample-tables

"ColorSchemeTypes": [
  "<ColorSchemeType ColorSchemeName=\"BHSampleTeal\">
    <ColorSchemeID>@id</ColorSchemeID>
    <Body1_Swap>0x37BEAE</Body1_Swap> ...
  </ColorSchemeType>"
]

ItemsVisualWeapon skins, avatars and emotesAlso emojis, sidekicks, KO effects, borders and titles. Each one starts as a copy of a game item.Details

How: Rows in weaponSkinTypes, avatarTypes, TauntTypes, EmojiTypes, SpawnBotTypes, TrailEffectTypes, SeasonBorderTypes or MonikerTypes.
In game: The normal loadout and podium pickers, already owned. Added podiums, player themes and companions are owned too.
Note: Emotes, sidekicks, KO effects and borders can go up to ID 1023.

sample-items

"weaponSkinTypes": [{ "copy": "HammerJade", "set": {
  "WeaponSkinName": "HammerBHSampleTeal",
  "WeaponSkinID": "@id", "DbID": "@id",
  "Weapon_Define": "0x1A8C82" } }],
"MonikerTypes": [{ "copy": "Birthday01", "set": {
  "@MonikerName": "BHSampleTitle", "MonikerID": "@id",
  "Color": "0x8FE3DA" } }]

LegendsGameplayNew legendsA new playable legend with its own name, stats, stances and default skin.Details

How: A HeroTypes row (stats have to add up to 22), a default skin in costumeTypes, ten RuneTypes stance rows, and default weaponSkinTypes for both weapons.
In game: The character select roster.
Limits: For now a new legend uses another legend's animations, weapons, portrait and sounds. tools/check_legend_mod.py runs the game's checks on it before you start the game.

sample-legend

"HeroTypes": [{ "copy": "Viking", "set": {
  "@HeroName": "BHSampleHero", "HeroID": "@id",
  "HeroDisplayName": "SAMPLE VIKING (MOD)",
  "Strength": "7", "Dexterity": "5",
  "Weight": "6", "Speed": "4" } }]

LegendsGameplayStats and stancesChange a legend's stance stats, or what a stat point does for everyone.Details

How: A stance row in RuneTypes for one legend's stance, or a StatTypes copy for a stat value.
Editor: The Move editor's LEGEND and STAT POINTS tabs do the same and save a mod.
In game: Any match with that legend, and the stance panel in the loadout window.

mod.json

"RuneTypes": [ { "stance": "Viking", "index": 0,
                 "set": { "Strength": "9" } } ],
"StatTypes": [ { "copy": "Speed5",
                 "set": { "RunSpeed": "50" } } ]

MovesGameplayMovesDamage, knockback, timing, hitboxes, movement and follow-ups. Around 3,700 moves.Details

How: powerTypes rows. Copy a move and set the columns you want to change (there are 184).
Editor: The Move editor in Training changes moves while you play, shows hitboxes, and saves a mod. There's also a web version on this site.
Note: You can't blank a column. Use 0.

mod.json

"powerTypes": [
  { "copy": "BaseNeutral",
    "set": { "BaseDamage": "30", "RecoverTime": "6" } }
]

ModesGameplayGame modesNew modes for Couch Party and custom rooms, based on an existing mode's rules.Details

How: A ScoringTypes row and a GameModeTypes row, usually copies of an existing mode. You can change lives, score to win, teams, items, timers, maps, icon, name and description.
In game: The mode list in Couch Party and custom rooms.
Bots: Bots know how to play King of the Hill style modes. Other new modes get normal bots.

sample-mode: King of the Hill

"ScoringTypes": [{ "copy": "COLORPLATFORMS", "set": {
  "@ScoringName": "BHKINGOFTHEHILL", "@Enabled": "True",
  "ScoringID": "@id", "IconName": "a_ScoringIcon_CLIMB" } }],
"GameModeTypes": [{ "copy": "DefaultColorPlatforms", "set": {
  "@GameModeName": "BHKingOfTheHill", "GameModeID": "@id",
  "ScoringType": "BHKINGOFTHEHILL" } }]

AnimationsGameplayAnimationsLoad an extra animation file after the game's to replace an animation.Details

How: A MasterFileList row pointing at an .anm file in your mod folder.
Note: There's no animation editor yet, so this one is harder.

sample-anim

"MasterFileList": [
  "<File Stage=\"Anim\" Name=\"mods/sample-anim/Animation_BHSample.anm\" ... />"
]

MapsGameplayNew mapsYour own stage with platforms, spawns, kill lines, art, music and bot paths.Details

How: A LevelDesc_*.xml layout listed in files, a LevelTypes row, and +Name added to the map lists it should be in.
Editor: The map editor (on this site too) lays it out, checks it, makes the bot paths and exports the mod.
Testing: F8 in the menus reloads map files, so you don't need to restart. The next match on that map uses your changes.

sample-map

"tables": {
  "LevelTypes": [ "<LevelType LevelName=\"BHSampleFlats\">
    <DisplayName>Sample Flats (mod)</DisplayName>
    <LevelID>@id</LevelID> ...</LevelType>" ],
  "LevelSetTypes": [ "<LevelSetType LevelSetName=\"StandardAll\">
    <LevelTypes>+BHSampleFlats</LevelTypes></LevelSetType>" ]
},
"files": [ "LevelDesc_BHSampleFlats.xml" ]

Map artVisualMap artDifferent art for the game's existing maps. Each player picks what they want per map.Details

How: A mapArt block: your art files (at the same paths as the game's), which maps they're for, and thumbnails.
In game: Mods > MAP ART. For each map pick the game's art, a mod's, shuffle (random each time) or mass (every piece random). Thumbnails and loading screens match.
Note: No restart needed to turn it on or off.

mod.json

"mapArt": {
  "files": [ "mapArt/Backgrounds/BG_Sakura.png" ],
  "maps": { "SmallBrawlhaven": "Sakura Brawlhaven" },
  "mapTypes": { "SmallBrawlhaven": [ "1v1" ] }
}

MusicVisualMusicMP3s for the menu, character select, results screen, maps, or any one track.Details

How: A music block with your tracks (title and volume are optional) and what they replace. *battle means every map.
Tool: tools/make_music_pack.py makes a music mod from a folder of MP3s.
In game: Mods > AUDIO lists every change and whether it's active. No restart needed.

sample-music

"music": {
  "tracks": {
    "calm": { "file": "music/quiet-a.mp3", "title": "Calm", "volume": 0.9 },
    "bright": "music/quiet-b.mp3"
  },
  "replaces": { "DefaultUI": "calm", "*battle": "bright" }
}

SoundsVisualSoundsReplace any sound: the announcer, menu sounds, hits, voices, moves.Details

How: A sounds block that maps a game sound event to your MP3.
Event names: Set "soundLog": true and the game logs every sound it plays. tools/sound_events.py lists them all.
Tool: tools/make_sound_pack.py makes a mod from MP3s named after their events.

mod.json

"sounds": {
  "VO_Announcer_InGame_Brawl_Play": "sounds/brawl.mp3"
}

TextVisualTextChange menu text, item names and descriptions, or add text for your own items.Details

How: strings, per language, using the game's text keys.
In game: Anywhere the game uses that key.

sample-strings

"strings": {
  "English": {
    "UI_MainMenu_Offline": "Offline (sample mod)"
  }
}

LanguagesVisualNew languagesAdd a language to the Language setting.Details

How: A LanguageTypes row (copied from an existing language) and strings under the new name.
Note: Fonts and untranslated text come from the language you copied, so stick to characters its fonts have.

sample-language: Pirate

"tables": { "LanguageTypes": [ { "copy": "English",
  "set": { "@LanguageName": "Pirate", "DnaCode": "en-PI" } } ] },
"strings": { "Pirate": {
  "UI_MainMenu_Play": "Set Sail", "UI_Back": "Belay" } }

Other data tables work the same way (map lists, custom game types, music, effect swaps and so on).

Example mods

These come with Bifrost in examples/mods. Copying one into your mods folder is a good way to start.

sample-stringsText

Changes the text of the main menu's Offline button.

sample-tablesColours

Adds a teal colour scheme and renames Bödvar on character select.

sample-languageLanguage

Adds Pirate, a copy of English with menu text reworded.

sample-skinSkin

Adds Sample Tealbear, a teal and gold Bödvar skin based on Bear.

sample-itemsItems

Adds a hammer, avatar, emote, emoji, sidekick, KO effect, border and title.

sample-legendLegend

Adds Sample Viking: own stats, stances, weapons and a green default skin.

sample-mapMap

Adds Sample Flats, a small map using the art from Plains of Passage.

sample-modeMode

Adds King of the Hill to Couch Party and custom rooms; the hill moves every 15 seconds.

sample-musicMusic

Replaces the menu and map music. Put your own MP3s in under the same names.

sample-animAnimation

Stretches Bödvar's hammer idle. Build its .anm from your own game files first.

sample-lone-kingCode mode

King of the Hill where the hill scores only while one team holds it alone. Needs a source build.

Editors and tools

The editors save normal mod folders, so you can turn them off or share them like any other mod.

Colour editor

Mods > COLOUR EDITOR

Hue, saturation and brightness for each part (hair, main, second, special, cloth, weapon, hands)
Edit single shades as RRGGBB
Preview on any legend and skin, idle or doing an emote or attack
Start from an existing scheme or import XML

→ mods\my-colors

Move editor

Training > Settings > PRACTICE

The common columns of a move, grouped, or all 184
Hitboxes shown on the legend, drag to move or resize, step through frames
Stance stats and stat points
Changes apply right away in Training

→ mods\my-moves or mods\moves-<name>

Web map editor

Bifrost > Map Editor on this site, or tools/map-editor

Platforms, collisions, spawns and art, using the same pieces the game's maps use
Drag the kill box, and all ~40 map settings have help text
Makes bot paths for you
A Check tab that finds problems and fixes most of them

→ <id>.zip, unzip it and press F8

Creator tool	What it does
tools/preview_content_mod.py	Applies your mods to the game's tables and prints what the game will do, before you start it.
tools/check_legend_mod.py	Runs the game's own legend, skin and stance checks on a legend mod.
tools/bmod_import.py	The same .bmod conversion the game does, from the command line. Also converts loose sound banks.
tools/make_music_pack.py	A folder of MP3s into a music mod (menu, character select, maps, victory).
tools/make_sound_pack.py	MP3s named after sound events into a sounds mod.
tools/sound_events.py	Lists every sound event name the game has.
tools/map-editor	The web map editor.

The Python tools are in Bifrost's source code. They read the game data from your own install.

mod.json reference

Mods load in a fixed order, requirements first and then by id, so the same mods give the same result on every PC.

Field	Does
id, name, version	Required. The id is what makes a mod unique: letters, digits, dot, dash, underscore.
author, description, preview	Shown in the Mods screen. preview is a PNG or JPG in the folder.
requires	Mod ids that must load first.
tables	Add or change rows of any game data table.
strings	Text, per language.
files	XML files such as map layouts.
assets	The game reads your file instead of one of its own.
palette	Shade-preserving colour schemes for a skin with its own art: each drawn shade (hex) lists its anchor colour (one of the skin's Define colours, hex) and its hue, lightness and saturation offsets from it.
animationAliases	Share another skin's lock-in and select animations.
soundBanks	Wwise sound banks in the mod folder.
mapArt, music, sounds	Art for existing maps, tracks, sound effects.

In a table	Means
"<Row ...>...</Row>"	An XML row in the game's own format. Same name as a game row: changes it. New name: adds it.
"a,b,c"	A CSV line in the table's column order.
{ "copy": "Name", "set": {...} }	Copy a game row and change only what you name. A new name makes a new row.
{ "add": "..." }	Added as it is, for tables whose rows have no name.
{ "stance": "Hero", "index": n, "set": {...} }	Change one stance of one legend.
@id · @id/Group	The next free ID, or the next free number within a group (a legend's skin slot).
+Name	Add to a list instead of replacing it, such as a map set.
@none	Empty a cell in a copied row.

Load report

Each start writes Documents\Bifrost\bh-mods.txt. Lines start with one of these.

loaded	The mod loaded.
skipped <why>	A missing or broken mod.json, a missing field, an id already used, or a missing requirement.
off	Switched off in the Mods screen.
conflict	Two mods change the same thing; the later one in load order wins.
row added / row changed	Every table row your mod touched.
renamed	Two mods added an item with the same name, so the later one was renamed.

If the game stops while loading, a row probably failed one of the game's checks: a missing field, stats that don't add up to 22, a legend with fewer than ten stances, or a map with no background or bot paths. Copying full rows and running the checker tools catches most of these.

Mod settings

In Documents\Bifrost\bh-mod-settings.json. Most of these are set from the Mods screen.

disabled	Mods you switched off in the Mods screen.
mapArt	Your art choice per map: default, a mod, shuffle or mass.
soundLog	true logs every sound event to Documents\Bifrost\bh-sounds.txt.
shareMods	false never offers to send your mods to a room.
hillBots	false turns off the hill-holding bots in King of the Hill style modes.

.bmod files

Community .bmod files are turned into normal Bifrost mods by the game itself. A skin from a .bmod is added as a new skin next to the one it was made for, so the original stays.

1
Add it
Drop the .bmod into the mods folder, or press IMPORT .BMOD on the Mods screen and pick it.
2
Converted
At the main menu the game converts it into a mod folder and moves the .bmod inside it. A popup lists what was added.
3
Restart
Map art works straight away. Skins, weapon skins and avatars show up after the game restarts.
4
Remove
Delete the mod's folder, or turn it off in the Installed tab like any other mod.

Works for skins, weapon skins, avatars and map art. Sound banks that come as loose .bnk files next to the .bmod aren't converted in game; tools/bmod_import.py still handles those. A file that can't be read stays in the mods folder and isn't tried again until it changes. Adding the same .bmod twice just says it's already imported.

Sharing mods

Bifrost servers have a mod library. Mods are only uploaded when you send them, and public ones have to be approved by the server's reviewers first.

1
Upload
Send a mod from the Mods screen, private or public. You need to be signed in with Discord.
2
Share key
Each upload gets a key like ABCD-2345. Anyone with the key can install it.
3
Review
Public mods wait until a reviewer tries them and approves or rejects them.
4
Community tab
Approved mods show up for everyone, sorted by likes and downloads.
5
Updates
People who got it from the Community tab get new versions automatically.

Servers only accept data, images, audio and art-only SWFs (no code). Limits: 64 MB per mod, 30 mods or 512 MB per account.

Mods online

VisualFine anywhere

Skins, colours, weapon skins, avatars, emotes, emojis, sidekicks, borders, KO effects, titles
Text, languages, map art, music and sounds
Other players see your item if they have the mod, otherwise the game item it was copied from

GameplayCustom rooms

Legends, stats, moves, game modes, maps, animations, any other table
Blocked in casual and ranked queues
In custom rooms everyone needs the same gameplay mods. The host can send theirs to the room
Shared replays remember their mods and offer to download them

Limits

New mods need a restart. Map art, music and sounds don't, and F8 reloads map files.
IDs are picked for you. Use @id and every PC gets the same number.
When two mods change the same thing, the one that loads later wins. The report lists these.
New legends reuse existing art. Animations, weapons, portrait and sounds come from the legend you copied.
Music has to be MP3. The welcome announcer line can't be replaced.
Mods can't contain code. New screens or new game rules need changes to Bifrost itself.
Only in Bifrost. The Official client doesn't support mods.
Mod items are unlocked. Anything a mod adds is owned as soon as it loads.