Lava is Floor is designed to be easy to make levels for, even without an in-game level editor. Levels are in the form of .zip files filled with a .json file with level pack information, and .svg files as the levels.

Levels are formatted in this way:

L0S - Solid Platforms for Level 0

L1D - Die Platforms for Level 1

L3P - Poison Platforms for Level 3

L0BG - Background for Level 0

Some other types include KD for key doors.

Fill your folder with  a Solids, Die, Poison, and Background for each level that needs it, and then add a .json file with level info.

The .json folder is structured like this:

{
  "record": "60", // The record to beat on the level for a S+
  "packname": "myawesomepack", // Will be used, make sure it's unique
  "startx0": "0", // When selecting levels, the starting position for this level (X)
  "starty0": "0", // In the game devkit, press C to change the starting position of the level in the JSON
  "startx1", "0",
  ...
  "key": {  // Stores positions for keys
    "1": {  // The level with keys in it
      "x": "0", // The X and Y of the key in this level
      "y": "0",
    },
    ...
  }
}

After filling the folder with these files, compress the folder to a .zip file, and change the extension to .liflevel, and your level pack is done! Make sure to test it in-game and make sure it works!