diff --git a/spark-fabric/build.gradle b/spark-fabric/build.gradle
index 6dfcb6d8..01149120 100644
--- a/spark-fabric/build.gradle
+++ b/spark-fabric/build.gradle
@@ -28,9 +28,9 @@ configurations {
 
 dependencies {
     // https://modmuss50.me/fabric.html
-    minecraft 'com.mojang:minecraft:1.20.6'
-    mappings 'net.fabricmc:yarn:1.20.6+build.1:v2'
-    modImplementation 'net.fabricmc:fabric-loader:0.15.10'
+    minecraft 'com.mojang:minecraft:1.21'
+    mappings 'net.fabricmc:yarn:1.21+build.1:v2'
+    modImplementation 'net.fabricmc:fabric-loader:0.15.11'
 
     Set<String> apiModules = [
             "fabric-api-base",
@@ -40,12 +40,12 @@ dependencies {
 
     // Add each module as a dependency
     apiModules.forEach {
-        modImplementation(fabricApi.module(it, '0.97.8+1.20.6'))
+        modImplementation(fabricApi.module(it, '0.100.1+1.21'))
     }
 
     include(modImplementation('me.lucko:fabric-permissions-api:0.3.1'))
 
-    modImplementation('eu.pb4:placeholder-api:2.4.0-pre.1+1.20.5')
+    modImplementation('eu.pb4:placeholder-api:2.4.0-pre.2+1.21')
 
     shade project(':spark-common')
 }
diff --git a/spark-fabric/src/main/java/me/lucko/spark/fabric/FabricWorldInfoProvider.java b/spark-fabric/src/main/java/me/lucko/spark/fabric/FabricWorldInfoProvider.java
index 156db89c..99da1fae 100644
--- a/spark-fabric/src/main/java/me/lucko/spark/fabric/FabricWorldInfoProvider.java
+++ b/spark-fabric/src/main/java/me/lucko/spark/fabric/FabricWorldInfoProvider.java
@@ -32,7 +32,6 @@
 import me.lucko.spark.fabric.mixin.ServerWorldAccessor;
 
 import net.minecraft.client.MinecraftClient;
-import net.minecraft.client.world.ClientEntityManager;
 import net.minecraft.client.world.ClientWorld;
 import net.minecraft.entity.Entity;
 import net.minecraft.entity.EntityType;
@@ -40,6 +39,7 @@
 import net.minecraft.server.world.ServerEntityManager;
 import net.minecraft.server.world.ServerWorld;
 import net.minecraft.util.math.ChunkPos;
+import net.minecraft.world.entity.ClientEntityManager;
 import net.minecraft.world.entity.EntityIndex;
 import net.minecraft.world.entity.EntityTrackingSection;
 import net.minecraft.world.entity.SectionedEntityCache;
diff --git a/spark-fabric/src/main/java/me/lucko/spark/fabric/mixin/ClientEntityManagerAccessor.java b/spark-fabric/src/main/java/me/lucko/spark/fabric/mixin/ClientEntityManagerAccessor.java
index 994c9a39..cc7de1f4 100644
--- a/spark-fabric/src/main/java/me/lucko/spark/fabric/mixin/ClientEntityManagerAccessor.java
+++ b/spark-fabric/src/main/java/me/lucko/spark/fabric/mixin/ClientEntityManagerAccessor.java
@@ -20,8 +20,8 @@
 
 package me.lucko.spark.fabric.mixin;
 
-import net.minecraft.client.world.ClientEntityManager;
 import net.minecraft.entity.Entity;
+import net.minecraft.world.entity.ClientEntityManager;
 import net.minecraft.world.entity.EntityIndex;
 import net.minecraft.world.entity.SectionedEntityCache;
 
diff --git a/spark-fabric/src/main/java/me/lucko/spark/fabric/mixin/ClientWorldAccessor.java b/spark-fabric/src/main/java/me/lucko/spark/fabric/mixin/ClientWorldAccessor.java
index 01562efe..ca790e94 100644
--- a/spark-fabric/src/main/java/me/lucko/spark/fabric/mixin/ClientWorldAccessor.java
+++ b/spark-fabric/src/main/java/me/lucko/spark/fabric/mixin/ClientWorldAccessor.java
@@ -20,10 +20,10 @@
 
 package me.lucko.spark.fabric.mixin;
 
-import net.minecraft.client.world.ClientEntityManager;
 import net.minecraft.client.world.ClientWorld;
 import net.minecraft.entity.Entity;
 
+import net.minecraft.world.entity.ClientEntityManager;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.gen.Accessor;
 
diff --git a/spark-fabric/src/main/java/me/lucko/spark/fabric/placeholder/SparkFabricPlaceholderApi.java b/spark-fabric/src/main/java/me/lucko/spark/fabric/placeholder/SparkFabricPlaceholderApi.java
index dc4321da..f269a199 100644
--- a/spark-fabric/src/main/java/me/lucko/spark/fabric/placeholder/SparkFabricPlaceholderApi.java
+++ b/spark-fabric/src/main/java/me/lucko/spark/fabric/placeholder/SparkFabricPlaceholderApi.java
@@ -42,7 +42,7 @@ public enum SparkFabricPlaceholderApi {
     public static void register(SparkPlatform platform) {
         for (SparkPlaceholder placeholder : SparkPlaceholder.values()) {
             Placeholders.register(
-                    new Identifier("spark", placeholder.getName()),
+                    Identifier.of("spark", placeholder.getName()),
                     new Handler(platform, placeholder)
             );
         }