diff --git a/src/main/java/net/neoforged/neoforge/registries/DeferredRegister.java b/src/main/java/net/neoforged/neoforge/registries/DeferredRegister.java
index 62f9501512..1c770e7e77 100644
--- a/src/main/java/net/neoforged/neoforge/registries/DeferredRegister.java
+++ b/src/main/java/net/neoforged/neoforge/registries/DeferredRegister.java
@@ -13,6 +13,7 @@ import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Objects;
 import java.util.Set;
+import java.util.function.BiFunction;
 import java.util.function.Consumer;
 import java.util.function.Function;
 import java.util.function.Supplier;
@@ -806,11 +807,27 @@ public class DeferredRegister<T> {
          * @param category The category of the entity, typically {@link MobCategory#MISC} for non-living entities, or one of the others for living entities.
          * @return A {@link DeferredHolder} which reflects the data that will be registered.
          * @param <E> the type of the entity
+         * @see #registerEntityType(String, EntityType.EntityFactory, MobCategory, BiFunction)
+         * @see #registerEntityType(String, EntityType.EntityFactory, MobCategory, UnaryOperator)
          */
         public <E extends Entity> DeferredHolder<EntityType<?>, EntityType<E>> registerEntityType(String name, EntityType.EntityFactory<E> factory, MobCategory category) {
             return this.registerEntityType(name, factory, category, UnaryOperator.identity());
         }
 
+        /// Convenience method that constructs a builder for use in the operator. Use this to avoid inference issues.
+        ///
+        /// @param name     The name for this entity type. It will automatically have the [namespace][#getNamespace()] prefixed.
+        /// @param factory  The factory used to typically construct the entity when using an existing helper from the type.
+        /// @param category The category of the entity, typically [MobCategory#MISC] for non-living entities, or one of the others for living entities.
+        /// @param builder  The bifunction that is passed `factory` and `category` and returns an [EntityType.Builder] which is built upon registration.
+        /// @return A [DeferredHolder] which reflects the data that will be registered.
+        /// @param <E> the type of the entity
+        /// @see #registerEntityType(String, EntityType.EntityFactory, MobCategory)
+        /// @see #registerEntityType(String, EntityType.EntityFactory, MobCategory, UnaryOperator)
+        public <E extends Entity> DeferredHolder<EntityType<?>, EntityType<E>> registerEntityType(String name, EntityType.EntityFactory<E> factory, MobCategory category, BiFunction<EntityType.EntityFactory<E>, MobCategory, EntityType.Builder<E>> builder) {
+            return this.register(name, key -> builder.apply(factory, category).build(ResourceKey.create(Registries.ENTITY_TYPE, key)));
+        }
+
         /**
          * Convenience method that constructs a builder for use in the operator. Use this to avoid inference issues.
          *
@@ -820,9 +837,11 @@ public class DeferredRegister<T> {
          * @param builder  The unary operator, which is passed a new builder for user operators, then builds it upon registration.
          * @return A {@link DeferredHolder} which reflects the data that will be registered.
          * @param <E> the type of the entity
+         * @see #registerEntityType(String, EntityType.EntityFactory, MobCategory)
+         * @see #registerEntityType(String, EntityType.EntityFactory, MobCategory, BiFunction)
          */
         public <E extends Entity> DeferredHolder<EntityType<?>, EntityType<E>> registerEntityType(String name, EntityType.EntityFactory<E> factory, MobCategory category, UnaryOperator<EntityType.Builder<E>> builder) {
-            return this.register(name, key -> builder.apply(EntityType.Builder.of(factory, category)).build(ResourceKey.create(Registries.ENTITY_TYPE, key)));
+            return this.registerEntityType(name, factory, category, (fact, cat) -> builder.apply(EntityType.Builder.of(fact, cat)));
         }
     }
 
diff --git a/testframework/src/main/java/net/neoforged/testframework/registration/DeferredEntityTypes.java b/testframework/src/main/java/net/neoforged/testframework/registration/DeferredEntityTypes.java
index 7148c74ce0..4c484d09c6 100644
--- a/testframework/src/main/java/net/neoforged/testframework/registration/DeferredEntityTypes.java
+++ b/testframework/src/main/java/net/neoforged/testframework/registration/DeferredEntityTypes.java
@@ -5,6 +5,7 @@
 
 package net.neoforged.testframework.registration;
 
+import java.util.function.BiFunction;
 import java.util.function.UnaryOperator;
 import net.minecraft.core.Registry;
 import net.minecraft.resources.Identifier;
@@ -27,6 +28,11 @@ public class DeferredEntityTypes extends DeferredRegister.Entities {
         return new DeferredEntityTypeBuilder(ResourceKey.create(registryKey, key), helper);
     }
 
+    @Override
+    public <E extends Entity> DeferredEntityTypeBuilder<E, EntityType<E>> registerEntityType(String name, EntityType.EntityFactory<E> factory, MobCategory category, BiFunction<EntityType.EntityFactory<E>, MobCategory, EntityType.Builder<E>> builder) {
+        return (DeferredEntityTypeBuilder<E, EntityType<E>>) super.registerEntityType(name, factory, category, builder);
+    }
+
     @Override
     public <E extends Entity> DeferredEntityTypeBuilder<E, EntityType<E>> registerEntityType(String name, EntityType.EntityFactory<E> factory, MobCategory category, UnaryOperator<EntityType.Builder<E>> builder) {
         return (DeferredEntityTypeBuilder<E, EntityType<E>>) super.registerEntityType(name, factory, category, builder);