--- a/net/minecraft/util/ClassInstanceMultiMap.java
+++ b/net/minecraft/util/ClassInstanceMultiMap.java
@@ -14,7 +_,7 @@
 import net.minecraft.Util;
 
 public class ClassInstanceMultiMap<T> extends AbstractCollection<T> {
-    private final Map<Class<?>, List<T>> byClass = Maps.newHashMap();
+    private final Map<Class<?>, List<T>> byClass = new it.unimi.dsi.fastutil.objects.Reference2ReferenceOpenHashMap<>(); // DivineMC - lithium: collections.entity_by_type
     private final Class<T> baseClass;
     private final List<T> allInstances = Lists.newArrayList();