diff --git a/src/main/java/de/bixilon/minosoft/data/registries/blocks/types/legacy/CustomBlockModel.kt b/src/main/java/de/bixilon/minosoft/data/registries/blocks/types/legacy/CustomBlockModel.kt
new file mode 100644
index 000000000..4f5312ec4
--- /dev/null
+++ b/src/main/java/de/bixilon/minosoft/data/registries/blocks/types/legacy/CustomBlockModel.kt
@@ -0,0 +1,22 @@
+/*
+ * Minosoft
+ * Copyright (C) 2020-2023 Moritz Zwerger
+ *
+ * This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * This software is not affiliated with Mojang AB, the original developer of Minecraft.
+ */
+
+package de.bixilon.minosoft.data.registries.blocks.types.legacy
+
+import de.bixilon.minosoft.data.registries.identified.ResourceLocation
+import de.bixilon.minosoft.protocol.versions.Version
+
+interface CustomBlockModel {
+    fun getModelName(version: Version) = modelName
+    val modelName: ResourceLocation? get() = null
+}
diff --git a/src/main/java/de/bixilon/minosoft/gui/rendering/models/loader/BlockLoader.kt b/src/main/java/de/bixilon/minosoft/gui/rendering/models/loader/BlockLoader.kt
index 98f378b48..4b3c09a36 100644
--- a/src/main/java/de/bixilon/minosoft/gui/rendering/models/loader/BlockLoader.kt
+++ b/src/main/java/de/bixilon/minosoft/gui/rendering/models/loader/BlockLoader.kt
@@ -38,7 +38,7 @@ class BlockLoader(private val loader: ModelLoader) {
     }
 
     fun loadState(block: Block): DirectBlockModel? {
-        val file = (if (block is CustomBlockModel) block.getModelName(version) else block.identifier).blockState()
+        val file = (if (block is CustomBlockModel) block.getModelName(version) else block.identifier)?.blockState() ?: return null
         val data = assets[file].readJsonObject()
 
         return DirectBlockModel.deserialize(this, data)