Asset Requirements

Good assets make the editors easier to use and make exported mods more reliable.

Goal

Prepare images and audio before importing them into a mod.

Images

  • Use PNG for sprites, portraits, previews, thumbnails, palettes, and most level art.
  • Prefer importing animated GIF for character and level animations.
  • Use transparency for character sprites, effects, pickups, and foreground objects that should not have a rectangular background.
  • Keep sprite scale consistent across a character. If one frame is drawn at a different scale, hitboxes and pivots become harder to tune.
  • Keep filenames simple. Short names using letters, numbers, spaces, hyphens, and underscores are easiest to manage.
  • Avoid resizing frames after you have tuned pivots, hitboxes, body boxes, or throw offsets.
  • For level art, prefer building a level from small reusable parts. Reuse background elements as possible. Consider building layers as tilemaps, using the grid feature in the editor. This makes levels faster to load when compared to using one single giant image for the entire scene.

Character frames

The Character Editor can import loose PNG files and animated GIF files. After import, check:

  • Pivot position on every frame.
  • Body box during idle, walking, jumping, attacking, being hit, and falling.
  • Hitboxes only on active attack frames.
  • Grab and throw offsets.
  • Weapon points or projectile spawn points when an animation uses them.

Characters with color palettes are converted to a maximum of 255 colors. If a character doesn't have at least one color palette (a default palette), then once exported, the community can't create new color palettes for it.

Palettes

  • Use palette images created by the editor whenever possible. It is, however, possible to create them manually using any image editing program. They are maximum 255 pixels width by 1 pixel height, one pixel per color.
  • Keep palette files in the correct target folder: entity-owned palettes under the entity folder, external palettes under Palettes/<Target Mod>/<Target Entity>.
  • Test every palette in-game using editor test mode, then verify the exported mod. A palette can look fine in isolation but clash with shadows, hit flashes, or HUD icons.

Audio

The Audio Editor accepts WAV, MP3, and OGG.

  • Use short files for hit sounds, voices, and menu sounds, typically as WAV.
  • Use music-length files for stage music and cutscene music, preferably OGG or MP3.
  • Set loop points for tracks that should loop cleanly.
  • Keep replacement audio names clear enough to identify the target sound or music.
  • Test volume in-game, not only in the editor preview.
  • Keep sounds and music files small, as they impact level loading times.

Scripts

Lua scripts are plain .lua files under Scripts.

  • Avoid renaming scripts once animation logic references them.
  • Prefer one clear behavior per script.
  • Test scripts with two or more players online, enemies on screen, and edge cases such as grabs, death, knockdown, and scene transitions.
  • Don't export and share mods with scripts until they are well tested. A faulty script may stale the game.