diff --git a/src/main/assets/JRE-17.zip b/src/main/assets/JRE-21.zip
similarity index 70%
rename from src/main/assets/JRE-17.zip
rename to src/main/assets/JRE-21.zip
index 4b8f269a..5e8ca320 100644
Binary files a/src/main/assets/JRE-17.zip and b/src/main/assets/JRE-21.zip differ
diff --git a/src/main/java/pojlib/UnityPlayerActivity.java b/src/main/java/pojlib/UnityPlayerActivity.java
index 81bdcad7..6ee1786e 100644
--- a/src/main/java/pojlib/UnityPlayerActivity.java
+++ b/src/main/java/pojlib/UnityPlayerActivity.java
@@ -53,15 +53,15 @@ protected String updateUnityCommandLineArguments(String cmdLine)
         mUnityPlayer = new UnityPlayer(this, this);
         setContentView(mUnityPlayer);
         mUnityPlayer.requestFocus();
-        File zip = new File(this.getFilesDir() + "/runtimes/JRE-17.zip");
+        File zip = new File(this.getFilesDir() + "/runtimes/JRE-21.zip");
         if(!zip.exists()) {
             try {
-                FileUtils.writeByteArrayToFile(zip, FileUtil.loadFromAssetToByte(this, "JRE-17.zip"));
+                FileUtils.writeByteArrayToFile(zip, FileUtil.loadFromAssetToByte(this, "JRE-21.zip"));
                 byte[] buffer = new byte[1024];
                 ZipInputStream zis = new ZipInputStream(Files.newInputStream(zip.toPath()));
                 ZipEntry zipEntry = zis.getNextEntry();
                 while (zipEntry != null) {
-                    File newFile = newFile(new File(this.getFilesDir() + "/runtimes/JRE-17"), zipEntry);
+                    File newFile = newFile(new File(this.getFilesDir() + "/runtimes/JRE-21"), zipEntry);
                     if (zipEntry.isDirectory()) {
                         if (!newFile.isDirectory() && !newFile.mkdirs()) {
                             throw new IOException("Failed to create directory " + newFile);
diff --git a/src/main/java/pojlib/util/JREUtils.java b/src/main/java/pojlib/util/JREUtils.java
index ee620464..37c292ed 100644
--- a/src/main/java/pojlib/util/JREUtils.java
+++ b/src/main/java/pojlib/util/JREUtils.java
@@ -130,7 +130,7 @@ public void run() {
     public static void relocateLibPath(final Context ctx) {
         sNativeLibDir = ctx.getApplicationInfo().nativeLibraryDir;
 
-        LD_LIBRARY_PATH = ctx.getFilesDir() + "/runtimes/JRE-17/bin" + "/lib64/jli:" + ctx.getFilesDir() + "/runtimes/JRE-17/lib:" +
+        LD_LIBRARY_PATH = ctx.getFilesDir() + "/runtimes/JRE-21/bin:" + ctx.getFilesDir() + "/runtimes/JRE-21/lib:" +
                 "/system/lib64:/vendor/lib64:/vendor/lib64/hw:" +
                 sNativeLibDir;
     }
@@ -138,14 +138,14 @@ public static void relocateLibPath(final Context ctx) {
     public static void setJavaEnvironment(Activity activity) throws Throwable {
         Map<String, String> envMap = new ArrayMap<>();
         envMap.put("POJLIB_NATIVEDIR", activity.getApplicationInfo().nativeLibraryDir);
-        envMap.put("JAVA_HOME", activity.getFilesDir() + "/runtimes/JRE-17");
+        envMap.put("JAVA_HOME", activity.getFilesDir() + "/runtimes/JRE-21");
         envMap.put("HOME", Constants.MC_DIR);
         envMap.put("TMPDIR", activity.getCacheDir().getAbsolutePath());
         envMap.put("VR_MODEL", API_V1.model);
         envMap.put("POJLIB_RENDERER", "regal");
 
         envMap.put("LD_LIBRARY_PATH", LD_LIBRARY_PATH);
-        envMap.put("PATH", activity.getFilesDir() + "/runtimes/JRE-17/bin:" + Os.getenv("PATH"));
+        envMap.put("PATH", activity.getFilesDir() + "/runtimes/JRE-21/bin:" + Os.getenv("PATH"));
 
         File customEnvFile = new File(Constants.USER_HOME, "custom_env.txt");
         if (customEnvFile.exists() && customEnvFile.isFile()) {
@@ -164,8 +164,8 @@ public static void setJavaEnvironment(Activity activity) throws Throwable {
             Os.setenv(env.getKey(), env.getValue(), true);
         }
 
-        File serverFile = new File(activity.getFilesDir() + "/runtimes/JRE-17/lib/server/libjvm.so");
-        jvmLibraryPath = activity.getFilesDir() + "/runtimes/JRE-17/lib/" + (serverFile.exists() ? "server" : "client");
+        File serverFile = new File(activity.getFilesDir() + "/runtimes/JRE-21/lib/server/libjvm.so");
+        jvmLibraryPath = activity.getFilesDir() + "/runtimes/JRE-21/lib/" + (serverFile.exists() ? "server" : "client");
         Log.d("DynamicLoader","Base LD_LIBRARY_PATH: "+LD_LIBRARY_PATH);
         Log.d("DynamicLoader","Internal LD_LIBRARY_PATH: "+jvmLibraryPath+":"+LD_LIBRARY_PATH);
         setLdLibraryPath(jvmLibraryPath+":"+LD_LIBRARY_PATH);
@@ -193,6 +193,9 @@ public static int launchJavaVM(final Activity activity, final List<String> JVMAr
             }
         }
 
+        userArgs.add("-XX:+UseZGC");
+        userArgs.add("-XX:+ZGenerational");
+
         userArgs.add("-Dorg.lwjgl.opengl.libname=" + graphicsLib);
         userArgs.add("-Dorg.lwjgl.opengles.libname=" + "/system/lib64/libGLESv3.so");
         userArgs.add("-Dorg.lwjgl.egl.libname=" + "/system/lib64/libEGL_dri.so");
@@ -201,7 +204,7 @@ public static int launchJavaVM(final Activity activity, final List<String> JVMAr
         userArgs.addAll(JVMArgs);
         System.out.println(JVMArgs);
 
-        runtimeDir = activity.getFilesDir() + "/runtimes/JRE-17";
+        runtimeDir = activity.getFilesDir() + "/runtimes/JRE-21";
 
         initJavaRuntime();
         chdir(Constants.MC_DIR);
@@ -220,7 +223,7 @@ public static int launchJavaVM(final Activity activity, final List<String> JVMAr
      */
     public static List<String> getJavaArgs(Context ctx) {
         return new ArrayList<>(Arrays.asList(
-                "-Djava.home=" + new File(ctx.getFilesDir(), "runtimes/JRE-17"),
+                "-Djava.home=" + new File(ctx.getFilesDir(), "runtimes/JRE-21"),
                 "-Djava.io.tmpdir=" + ctx.getCacheDir().getAbsolutePath(),
                 "-Duser.home=" + Constants.MC_DIR,
                 "-Duser.language=" + System.getProperty("user.language"),