diff --git a/WeaveLoader.API/WeaveLoader.API.csproj b/WeaveLoader.API/WeaveLoader.API.csproj
index aec1805..8d097bf 100644
--- a/WeaveLoader.API/WeaveLoader.API.csproj
+++ b/WeaveLoader.API/WeaveLoader.API.csproj
@@ -13,4 +13,12 @@
     <AppendRuntimeIdentifierToOutputPath>false</AppendRuntimeIdentifierToOutputPath>
   </PropertyGroup>
 
+  <!-- Mod textures: use Target so they only copy when API builds to mods/, not when copied as dependency -->
+  <Target Name="CopyModAssets" AfterTargets="Build">
+    <MakeDir Directories="$(OutputPath)assets\blocks" />
+    <MakeDir Directories="$(OutputPath)assets\items" />
+    <Copy SourceFiles="mod_assets\blocks\missing_block.png" DestinationFolder="$(OutputPath)assets\blocks\" SkipUnchangedFiles="true" />
+    <Copy SourceFiles="mod_assets\items\missing_item.png" DestinationFolder="$(OutputPath)assets\items\" SkipUnchangedFiles="true" />
+  </Target>
+
 </Project>
diff --git a/WeaveLoader.API/mod_assets/README.md b/WeaveLoader.API/mod_assets/README.md
new file mode 100644
index 0000000..00139c2
--- /dev/null
+++ b/WeaveLoader.API/mod_assets/README.md
@@ -0,0 +1,10 @@
+# WeaveLoader.API Mod Assets
+
+Placeholder textures for the missing block and missing item (unresolved mod content).
+Stored in `mod_assets/` to avoid conflict with the `Assets/` C# source folder (Windows case-insensitivity).
+Copied to `assets/blocks/` and `assets/items/` in the build output.
+
+- **Blocks:** `mod_assets/blocks/missing_block.png` → icon `weaveloader.api:missing_block`
+- **Items:** `mod_assets/items/missing_item.png` → icon `weaveloader.api:missing_item`
+
+These are used when a world contains blocks or items from mods that are no longer installed.
diff --git a/WeaveLoader.API/mod_assets/blocks/missing_block.png b/WeaveLoader.API/mod_assets/blocks/missing_block.png
new file mode 100644
index 0000000..c5d9aef
Binary files /dev/null and b/WeaveLoader.API/mod_assets/blocks/missing_block.png differ
diff --git a/WeaveLoader.API/mod_assets/items/missing_item.png b/WeaveLoader.API/mod_assets/items/missing_item.png
new file mode 100644
index 0000000..b8a13ce
Binary files /dev/null and b/WeaveLoader.API/mod_assets/items/missing_item.png differ
diff --git a/WeaveLoaderRuntime/src/WorldIdRemap.cpp b/WeaveLoaderRuntime/src/WorldIdRemap.cpp
index 63fd5af..d7d0b4d 100644
--- a/WeaveLoaderRuntime/src/WorldIdRemap.cpp
+++ b/WeaveLoaderRuntime/src/WorldIdRemap.cpp
@@ -662,7 +662,7 @@ namespace WorldIdRemap
                 1.0f,
                 1.0f,
                 1,
-                L"bedrock",
+                L"weaveloader.api:missing_block",
                 0.0f,
                 15,
                 kMissingBlockDescriptionId);
@@ -676,7 +676,7 @@ namespace WorldIdRemap
                 missingItemId,
                 64,
                 0,
-                L"apple",
+                L"weaveloader.api:missing_item",
                 kMissingItemDescriptionId);
             IdRegistry::Instance().SetMissingFallback(IdRegistry::Type::Item, missingItemId);
         }