diff --git a/src/AcDream.App/Rendering/StaticMeshRenderer.cs b/src/AcDream.App/Rendering/StaticMeshRenderer.cs
index 6a2da70..135af25 100644
--- a/src/AcDream.App/Rendering/StaticMeshRenderer.cs
+++ b/src/AcDream.App/Rendering/StaticMeshRenderer.cs
@@ -135,6 +135,30 @@ public sealed unsafe class StaticMeshRenderer : IDisposable
         _gl.Enable(EnableCap.Blend);
         _gl.DepthMask(false);
 
+        // Phase 9.2: enable back-face culling for the translucent pass so
+        // closed-shell translucents (lifestone crystal, glow gems, any
+        // convex blended mesh) don't draw their back faces over their
+        // front faces in arbitrary iteration order. Without this, the
+        // 58 triangles of the lifestone crystal composited with an
+        // "inside-out" look where the user saw through one face into
+        // the hollow interior. With back-face culling on, back faces are
+        // dropped at rasterization time, front faces composite as-is,
+        // and depth ordering within the front-facing subset is a
+        // non-issue for closed convex-ish shells. Matches WorldBuilder's
+        // per-batch CullMode handling in
+        // references/WorldBuilder/Chorizite.OpenGLSDLBackend/Lib/
+        // BaseObjectRenderManager.cs:361-365.
+        //
+        // Our fan triangulation emits pos-side polygons as
+        // (0, i, i+1) which is CCW in standard OpenGL conventions, so
+        // GL_BACK + CCW front is the correct state. Neg-side polygons
+        // (if any) use reversed winding and get culled here — that's a
+        // known limitation and matches the opaque-pass behavior since
+        // neg-side polys are virtually never translucent in AC content.
+        _gl.Enable(EnableCap.CullFace);
+        _gl.CullFace(TriangleFace.Back);
+        _gl.FrontFace(FrontFaceDirection.Ccw);
+
         foreach (var entity in entityList)
         {
             if (entity.MeshRefs.Count == 0)
@@ -191,6 +215,7 @@ public sealed unsafe class StaticMeshRenderer : IDisposable
         // Restore default GL state for subsequent renderers (terrain etc.).
         _gl.DepthMask(true);
         _gl.Disable(EnableCap.Blend);
+        _gl.Disable(EnableCap.CullFace);
 
         _gl.BindVertexArray(0);
     }