Replacing game files

Put a file under MBTL-IM\Mods at the same path it has inside the game's archives.

File in Mods	What it does
`bg\BgList.txt`	the stage table
`bg\BgList_str.ini`	stage names
`bg\bg036\bg.fbx.bin`	stage 36's model
`bg\bg65535\stage_color.img`	character select lighting
`Bgm\bgm.txt`	the music table

The first time the game reads its stage list, the mod saves the game's own bg\BgList.txt and bg\BgList_str.ini to MBTL-IM\Mods\bg as plain text. From then on those copies are the stage list. After a game update, delete them and start the game once to get fresh copies.

Stage values without editing BgList.txt

A stage.txt in a stage folder holds the values that would otherwise go in its Bg_ block of BgList.txt:

Name = "My stage"
FOV = 43.0,
ShadowLightType = 0,
ShadowLightStatus =
[
	{ Type=1, Position=0.0, PowerValue=7.0, Color=[0.0,0.0,0.0,0.8] },
],
StageSelTex = 45,

A whole Bg_090 = { ... } block copied from BgList.txt works too.

In a stage folder you import (Stages > Add stages > A stage folder of your own), every value is used.
In Mods\bg\bgNNN\stage.txt for one of the game's own stage numbers, it changes that stage.

StageW is the one value that is never used. Every stage keeps the game's wall distance (StageW = 4096), so both players always have the same walls online.

Replacing one of the game's stages

Stages > Add stages > In place of one of the game's stages copies a stage folder over a stage the game already has. The stage keeps its number, card and music, so it needs no free number. An opponent who does not have it plays the game's stage instead of crashing. The walls and the selection flags stay the game's, so the match stays in sync.

Restore, under Installed stages, brings the game's stage back.

Stage select cards

Put a thumbnail.png or thumbnail.dds next to bg.fbx.bin. The mod paints it into the stage select and points the stage at it. Any size works: it is scaled to fill the card and cut to the card's shape. An image of exactly 144x336 is used as it is, transparency included. DDS files can be uncompressed, DXT1 or DXT5.

A stage with a thumbnail always uses it as its card. A stage without one uses the card picked in the Stages window, then its StageSelTex, then stage 1's card. Changes show after a restart.

By hand: StageSelTex 0 to 20 are on grpdat\CSel\stage_thumb00.dds, 21 and up on stage_thumb01.dds, seven cards per row of 144x336 pixels. The game's own art stops at card 30. To add rows, make MBTL-IM\Mods\grpdat\CSel\stage_thumb01.dds taller with a power of two height: 1024x2048 reaches card 62.

VS screen and main menu pictures

Two more pictures can sit next to bg.fbx.bin, as PNG or DDS:

File	Where it shows	Best size
`vs_background.png`	behind the characters before a match	2:1, such as 2048x1024
`menu_background.png`	the main menu background	16:9, such as 1920x1080

Keep the important part of the VS picture away from the top and bottom edges, the game fades them out. The main menu shows a random stage, so a stage only appears there when the random stage filter allows it. To test a menu picture, pick the stage in Stages > Installed stages > Main menu background, then open the main menu. Set it back to Game default when you are done.

For each stage the mod picks, in this order: the picture in the stage folder, a menu_bgNN.pat or vs_demo_bgNN.pat from another mod, the game's own file, and finally stage 1's picture, so the screen is never black or empty. A picture in Mods\bg\bgNNN for one of the game's own stage numbers replaces that stage's picture too. Changes show after a restart.

Darker characters on a stage

Add this line to a stage's stage.txt:

CharaTint = 0x141414

On that stage the characters are drawn in that colour, like the dark silhouettes of Last corridor. The value is a colour written as 0xRRGGBB: 0x000000 is black, 0x808080 is half dark, 0xFFFFFF changes nothing. It only works offline, and moves that change the character's colour themselves are covered while the tint is on.

Removing a stage

Remove, under Installed stages, deletes the stage's folder and takes it off the list right away. The game still lists it until you restart, so do not pick it before then.

Rules

Files are plain and unencrypted, the same files an unpacker writes out.
New files work too, not only replacements, so new stages can be added.
Two mods that change the same file, such as bg\BgList.txt, have to be merged by hand.

The log

MBTL-IM\Logs holds one log per launch. It shows whether the loader found the game's file reader, every file it served, and every file the game looked for in a modded folder but did not find. If a game update breaks the loader, it turns itself off, the game runs unmodded, and the log says why.