diff --git a/Penumbra.GameData/Files/MtrlFile.Write.cs b/Penumbra.GameData/Files/MtrlFile.Write.cs
new file mode 100644
index 00000000..910854b9
--- /dev/null
+++ b/Penumbra.GameData/Files/MtrlFile.Write.cs
@@ -0,0 +1,96 @@
+using System.IO;
+using System.Linq;
+using System.Text;
+
+namespace Penumbra.GameData.Files;
+
+public partial class MtrlFile
+{
+    public byte[] Write()
+    {
+        using var stream = new MemoryStream();
+        using( var w = new BinaryWriter( stream ) )
+        {
+            const int materialHeaderSize = 4 + 2 + 2 + 2 + 2 + 1 + 1 + 1 + 1;
+
+            w.BaseStream.Seek( materialHeaderSize, SeekOrigin.Begin );
+            ushort cumulativeStringOffset = 0;
+            foreach( var texture in Textures )
+            {
+                w.Write( cumulativeStringOffset );
+                w.Write( texture.Flags );
+                cumulativeStringOffset += ( ushort )( texture.Path.Length + 1 );
+            }
+
+            foreach( var colorSet in UvColorSets.Concat( ColorSets ) )
+            {
+                w.Write( cumulativeStringOffset );
+                w.Write( colorSet.Index );
+                cumulativeStringOffset += ( ushort )( colorSet.Name.Length + 1 );
+            }
+
+            foreach( var text in Textures.Select( t => t.Path )
+                       .Concat( UvColorSets.Concat( ColorSets ).Select( c => c.Name ).Append( ShaderPackage.Name ) ) )
+            {
+                w.Write( Encoding.UTF8.GetBytes( text ) );
+                w.Write( ( byte )'\0' );
+            }
+
+            w.Write( AdditionalData );
+            foreach( var color in ColorSetData )
+            {
+                w.Write( color );
+            }
+
+            w.Write( ( ushort )( ShaderPackage.ShaderValues.Length * 4 ) );
+            w.Write( ( ushort )ShaderPackage.ShaderKeys.Length );
+            w.Write( ( ushort )ShaderPackage.Constants.Length );
+            w.Write( ( ushort )ShaderPackage.Samplers.Length );
+            w.Write( ShaderPackage.Unk );
+
+            foreach( var key in ShaderPackage.ShaderKeys )
+            {
+                w.Write( key.Category );
+                w.Write( key.Value );
+            }
+
+            foreach( var constant in ShaderPackage.Constants )
+            {
+                w.Write( constant.Id );
+                w.Write( constant.Value );
+            }
+
+            foreach( var sampler in ShaderPackage.Samplers )
+            {
+                w.Write( sampler.SamplerId );
+                w.Write( sampler.Flags );
+                w.Write( sampler.TextureIndex );
+                w.Write( ( ushort )0 );
+                w.Write( ( byte )0 );
+            }
+
+            foreach( var value in ShaderPackage.ShaderValues )
+            {
+                w.Write( value );
+            }
+
+            WriteHeader( w, ( ushort )w.BaseStream.Position, cumulativeStringOffset );
+        }
+
+        return stream.ToArray();
+    }
+
+    private void WriteHeader( BinaryWriter w, ushort fileSize, ushort shaderPackageNameOffset )
+    {
+        w.BaseStream.Seek( 0, SeekOrigin.Begin );
+        w.Write( Version );
+        w.Write( fileSize );
+        w.Write( ( ushort )( ColorSetData.Length * 2 ) );
+        w.Write( ( ushort )( shaderPackageNameOffset + ShaderPackage.Name.Length + 1 ) );
+        w.Write( shaderPackageNameOffset );
+        w.Write( ( byte )Textures.Length );
+        w.Write( ( byte )UvColorSets.Length );
+        w.Write( ( byte )ColorSets.Length );
+        w.Write( ( byte )AdditionalData.Length );
+    }
+}
\ No newline at end of file
diff --git a/Penumbra.GameData/Files/MtrlFile.cs b/Penumbra.GameData/Files/MtrlFile.cs
new file mode 100644
index 00000000..5d6d81a0
--- /dev/null
+++ b/Penumbra.GameData/Files/MtrlFile.cs
@@ -0,0 +1,133 @@
+using System;
+using System.IO;
+using System.Text;
+using Lumina.Data.Parsing;
+using Lumina.Extensions;
+
+namespace Penumbra.GameData.Files;
+
+public partial class MtrlFile
+{
+    public struct ColorSet
+    {
+        public string Name;
+        public ushort Index;
+    }
+
+    public struct Texture
+    {
+        public string Path;
+        public ushort Flags;
+    }
+
+    public struct Constant
+    {
+        public uint Id;
+        public uint Value;
+    }
+
+    public struct ShaderPackageData
+    {
+        public string      Name;
+        public ShaderKey[] ShaderKeys;
+        public Constant[]  Constants;
+        public Sampler[]   Samplers;
+        public float[]     ShaderValues;
+        public uint        Unk;
+    }
+
+
+    public uint Version;
+
+    public Texture[]         Textures;
+    public ColorSet[]        UvColorSets;
+    public ColorSet[]        ColorSets;
+    public ushort[]          ColorSetData;
+    public ShaderPackageData ShaderPackage;
+    public byte[]            AdditionalData;
+
+    public MtrlFile( byte[] data )
+    {
+        using var stream = new MemoryStream( data );
+        using var r      = new BinaryReader( stream );
+
+        Version = r.ReadUInt32();
+        r.ReadUInt16(); // file size
+        var dataSetSize             = r.ReadUInt16();
+        var stringTableSize         = r.ReadUInt16();
+        var shaderPackageNameOffset = r.ReadUInt16();
+        var textureCount            = r.ReadByte();
+        var uvSetCount              = r.ReadByte();
+        var colorSetCount           = r.ReadByte();
+        var additionalDataSize      = r.ReadByte();
+
+        Textures    = ReadTextureOffsets( r, textureCount, out var textureOffsets );
+        UvColorSets = ReadColorSetOffsets( r, uvSetCount, out var uvOffsets );
+        ColorSets   = ReadColorSetOffsets( r, colorSetCount, out var colorOffsets );
+
+        var strings = r.ReadBytes( stringTableSize );
+        for( var i = 0; i < textureCount; ++i )
+        {
+            Textures[ i ].Path = UseOffset( strings, textureOffsets[ i ] );
+        }
+
+        for( var i = 0; i < uvSetCount; ++i )
+        {
+            UvColorSets[ i ].Name = UseOffset( strings, uvOffsets[ i ] );
+        }
+
+        for( var i = 0; i < colorSetCount; ++i )
+        {
+            ColorSets[ i ].Name = UseOffset( strings, colorOffsets[ i ] );
+        }
+
+        ShaderPackage.Name = UseOffset( strings, shaderPackageNameOffset );
+
+        AdditionalData = r.ReadBytes( additionalDataSize );
+        ColorSetData   = r.ReadStructuresAsArray< ushort >( dataSetSize / 2 );
+
+        var shaderValueListSize = r.ReadUInt16();
+        var shaderKeyCount      = r.ReadUInt16();
+        var constantCount       = r.ReadUInt16();
+        var samplerCount        = r.ReadUInt16();
+        ShaderPackage.Unk = r.ReadUInt32();
+
+        ShaderPackage.ShaderKeys   = r.ReadStructuresAsArray< ShaderKey >( shaderKeyCount );
+        ShaderPackage.Constants    = r.ReadStructuresAsArray< Constant >( constantCount );
+        ShaderPackage.Samplers     = r.ReadStructuresAsArray< Sampler >( samplerCount );
+        ShaderPackage.ShaderValues = r.ReadStructuresAsArray< float >( shaderValueListSize / 4 );
+    }
+
+    private static Texture[] ReadTextureOffsets( BinaryReader r, int count, out ushort[] offsets )
+    {
+        var ret = new Texture[count];
+        offsets = new ushort[count];
+        for( var i = 0; i < count; ++i )
+        {
+            offsets[ i ]   = r.ReadUInt16();
+            ret[ i ].Flags = r.ReadUInt16();
+        }
+
+        return ret;
+    }
+
+    private static ColorSet[] ReadColorSetOffsets( BinaryReader r, int count, out ushort[] offsets )
+    {
+        var ret = new ColorSet[count];
+        offsets = new ushort[count];
+        for( var i = 0; i < count; ++i )
+        {
+            offsets[ i ]   = r.ReadUInt16();
+            ret[ i ].Index = r.ReadUInt16();
+        }
+
+        return ret;
+    }
+
+    private static string UseOffset( ReadOnlySpan< byte > strings, ushort offset )
+    {
+        strings = strings[ offset.. ];
+        var end = strings.IndexOf( ( byte )'\0' );
+        return Encoding.UTF8.GetString( strings[ ..end ] );
+    }
+}
\ No newline at end of file