Asset Overview

File Formats

Hytale uses several custom file formats alongside standard ones:

JSON Configuration (`.json`)

The primary format for all game data. Used for:

NPC role definitions
Item and block definitions
Recipes and loot tables
Spawn rules and world generation
Model definitions (server-side)
Gameplay configurations

Blocky Model (`.blockymodel`)

Hytale’s 3D model format. JSON-based internally, containing:

Cuboid geometry (position, size, rotation)
UV mapping to texture sheets
Bone hierarchy for animation
Attachment points for equipment

Created and edited with Blockbench using the Hytale plugin.

Blocky Animation (`.blockyanim`)

Hytale’s animation format. JSON-based, containing:

Keyframe data for bones
Position, rotation, and scale channels
Loop settings and timing

Textures (`.png`)

Standard PNG images used for:

Block faces
Model textures (resolution varies by model complexity)
UI elements and icons
Particle effects

Hytale uses pixel-art style textures. Common resolutions:

32 px density — Standard cube blocks
64 px density — Player models and most character-scale equipment
64 px density (best current assumption) — NPCs and mobs, based on the Hytale Modding community reference

When choosing a texture size, match the target asset’s pixel density first. For example, a block face may be 32x32, while a character sheet may be 64x64 or 128x128 if it preserves the same density.

Key Concepts

Namespace

Every asset is identified by its mod namespace: Group:Name. For example, Hytale:Sword_Iron refers to the iron sword in the base game.

Inheritance

Many JSON files support inheritance via Parent or Reference fields. This lets you create new content by extending existing definitions rather than writing everything from scratch. See Inheritance and Templates for details.

Localization

All player-facing text uses translation keys rather than hardcoded strings. Keys are defined in .lang files under the Languages/ directories. See Localization Keys for the format.