diff --git a/common/src/main/java/com/adamcalculator/dynamicpack/Mod.java b/common/src/main/java/com/adamcalculator/dynamicpack/Mod.java
index 830d46e..0ba75eb 100644
--- a/common/src/main/java/com/adamcalculator/dynamicpack/Mod.java
+++ b/common/src/main/java/com/adamcalculator/dynamicpack/Mod.java
@@ -8,12 +8,19 @@
 import java.util.Set;
 
 public class Mod {
+    public static final String VERSION_NAME_MOD = "1.0.13";
+    public static final String VERSION_NAME_BRANCH = "mc1.20.1";
+    public static final String VERSION_NAME =  VERSION_NAME_MOD + "-" + VERSION_NAME_BRANCH;
+    public static final long VERSION_BUILD = 14;
+
+
     // NOTE: for increase contact to mod developer.
     public static final long DYNAMIC_PACK_HTTPS_FILE_SIZE_LIMIT = megabyte(8); // kb -> mb -> 5MB (for files in resourcepack)
     public static final long MODRINTH_HTTPS_FILE_SIZE_LIMIT = megabyte(1024); // 1 GB (for .zip files from modrinth)
     public static final long MOD_MODTINTH_API_LIMIT = megabyte(8); // 8 MB of api
     public static final long GZIP_LIMIT = megabyte(50); // 50 MB of .gz file
     public static final long MOD_FILES_LIMIT = megabyte(8);
+    public static final String MODRINTH_URL = "https://modrinth.com/mod/dynamicpack";
 
     private static final Set<String> ALLOWED_HOSTS = new HashSet<>();
     static {
diff --git a/common/src/main/java/com/adamcalculator/dynamicpack/pack/Pack.java b/common/src/main/java/com/adamcalculator/dynamicpack/pack/Pack.java
index 90ada74..7d9740b 100644
--- a/common/src/main/java/com/adamcalculator/dynamicpack/pack/Pack.java
+++ b/common/src/main/java/com/adamcalculator/dynamicpack/pack/Pack.java
@@ -2,6 +2,7 @@
 
 import com.adamcalculator.dynamicpack.DynamicPackModBase;
 import com.adamcalculator.dynamicpack.PackUtil;
+import com.adamcalculator.dynamicpack.status.StatusChecker;
 import com.adamcalculator.dynamicpack.sync.PackSyncProgress;
 import com.adamcalculator.dynamicpack.util.AFiles;
 import com.adamcalculator.dynamicpack.util.Out;
@@ -50,6 +51,12 @@ public boolean isSyncing() {
         return isSyncing;
     }
 
+    // See StatusChecker for this.
+    // Developer can block network for specify version in dynamicpack.status.v1.json by security questions
+    public boolean isNetworkBlocked() {
+        return StatusChecker.isBlockUpdating(remoteTypeStr);
+    }
+
     public boolean isZip() {
         if (location.isDirectory()) {
             return false;
@@ -84,6 +91,7 @@ public long getLatestUpdated() {
     }
 
     public boolean checkIsUpdateAvailable() throws IOException {
+        checkNetwork();
         return cachedUpdateAvailable = remote.checkUpdateAvailable();
     }
 
@@ -108,6 +116,9 @@ private void sync0(PackSyncProgress progress, boolean manually) throws Exception
             progress.done(false);
             return;
         }
+
+        checkNetwork();
+
         if (!checkIsUpdateAvailable() && !manually) {
             progress.textLog("update not available");
             progress.done(false);
@@ -124,6 +135,12 @@ private void sync0(PackSyncProgress progress, boolean manually) throws Exception
         progress.done(reloadRequired);
     }
 
+    private void checkNetwork() {
+        if (isNetworkBlocked()) {
+            throw new SecurityException("Network is blocked for remote_type: " + remoteTypeStr + " in dynamicpack.status.v1.json by security questions!");
+        }
+    }
+
     private void checkSafePackMinecraftMeta() throws IOException {
         PackUtil.openPackFileSystem(location, path -> {
             Path mcmeta = path.resolve(DynamicPackModBase.MINECRAFT_META);
diff --git a/common/src/main/java/com/adamcalculator/dynamicpack/status/StatusChecker.java b/common/src/main/java/com/adamcalculator/dynamicpack/status/StatusChecker.java
new file mode 100644
index 0000000..87e7898
--- /dev/null
+++ b/common/src/main/java/com/adamcalculator/dynamicpack/status/StatusChecker.java
@@ -0,0 +1,53 @@
+package com.adamcalculator.dynamicpack.status;
+
+import com.adamcalculator.dynamicpack.Mod;
+import com.adamcalculator.dynamicpack.util.Out;
+import com.adamcalculator.dynamicpack.util.Urls;
+import org.json.JSONObject;
+
+public class StatusChecker {
+    private static final String URL = "https://adamcalculator.github.io/DynamicPack/dynamicpack.status.v1.json";
+
+
+    private static boolean isUpdateAvailable = false;
+    private static boolean isFormatActual = true;
+    private static boolean isSafe = true;
+    private static boolean isChecked = false;
+
+    public static void check() throws Exception {
+        Out.println("Checking status...");
+        String s = Urls.parseContent(URL, 1024 * 1024 * 128);
+        JSONObject j = new JSONObject(s);
+        JSONObject lat = j.getJSONObject("latest_version");
+        isUpdateAvailable = lat.getLong("build") > Mod.VERSION_BUILD;
+        isSafe = lat.getLong("safe") <= Mod.VERSION_BUILD;
+        isFormatActual = lat.getLong("format") <= Mod.VERSION_BUILD;
+
+        isChecked = true;
+        Out.println(String.format("Status checked! isSafe=%s, isFormatActual=%s, isUpdateAvailable=%s", isSafe, isFormatActual, isUpdateAvailable));
+    }
+
+    public static boolean isBlockUpdating(String remoteType) {
+        if (remoteType.equals("modrinth")) {
+            return false;
+        }
+        return !isSafe();
+    }
+
+
+    public static boolean isModUpdateAvailable() {
+        return isUpdateAvailable;
+    }
+
+    public static boolean isSafe() {
+        return isSafe;
+    }
+
+    public static boolean isFormatActual() {
+        return isFormatActual;
+    }
+
+    public static boolean isChecked() {
+        return isChecked;
+    }
+}
diff --git a/common/src/main/java/com/adamcalculator/dynamicpack/sync/SyncThread.java b/common/src/main/java/com/adamcalculator/dynamicpack/sync/SyncThread.java
index d8e2894..e01cf56 100644
--- a/common/src/main/java/com/adamcalculator/dynamicpack/sync/SyncThread.java
+++ b/common/src/main/java/com/adamcalculator/dynamicpack/sync/SyncThread.java
@@ -1,5 +1,8 @@
 package com.adamcalculator.dynamicpack.sync;
 
+import com.adamcalculator.dynamicpack.status.StatusChecker;
+import com.adamcalculator.dynamicpack.util.Out;
+
 import java.util.function.Supplier;
 
 public class SyncThread extends Thread {
@@ -10,6 +13,9 @@ public class SyncThread extends Thread {
 
     public SyncThread(Supplier<SyncingTask> taskSupplier) {
         super("SyncThread" + (counter++));
+        if (counter > 1) {
+            Out.warn("Multiple SyncThread's is bad behavior...");
+        }
         this.taskSupplier = taskSupplier;
     }
 
@@ -27,6 +33,11 @@ public void run() {
 
 
     private void startSync() {
+        try {
+            StatusChecker.check();
+        } catch (Exception e) {
+            Out.error("Error while check status!", e);
+        }
         taskSupplier.get().run();
     }
 }
diff --git a/common/src/main/java/com/adamcalculator/dynamicpack/util/Out.java b/common/src/main/java/com/adamcalculator/dynamicpack/util/Out.java
index cf627f6..cbf7e20 100644
--- a/common/src/main/java/com/adamcalculator/dynamicpack/util/Out.java
+++ b/common/src/main/java/com/adamcalculator/dynamicpack/util/Out.java
@@ -16,7 +16,7 @@ public static void println(Object o) {
             System.out.println(o);
             return;
         }
-        LOGGER.warn(o + "");
+        LOGGER.info(o + "");
     }
 
     public static void error(String s, Exception e) {
diff --git a/src/client/java/com/adamcalculator/dynamicpack/FabricDynamicMod.java b/src/client/java/com/adamcalculator/dynamicpack/FabricDynamicMod.java
index d253bd6..95c05c1 100644
--- a/src/client/java/com/adamcalculator/dynamicpack/FabricDynamicMod.java
+++ b/src/client/java/com/adamcalculator/dynamicpack/FabricDynamicMod.java
@@ -1,23 +1,30 @@
 package com.adamcalculator.dynamicpack;
 
 import com.adamcalculator.dynamicpack.pack.Pack;
+import com.adamcalculator.dynamicpack.status.StatusChecker;
 import com.adamcalculator.dynamicpack.sync.SyncThread;
 import com.adamcalculator.dynamicpack.sync.SyncingTask;
 import com.adamcalculator.dynamicpack.sync.state.StateDownloading;
 import com.adamcalculator.dynamicpack.sync.state.StateFileDeleted;
 import com.adamcalculator.dynamicpack.sync.state.SyncProgressState;
+import com.adamcalculator.dynamicpack.util.Out;
 import net.fabricmc.api.ClientModInitializer;
+import net.fabricmc.fabric.api.client.networking.v1.ClientPlayConnectionEvents;
 import net.fabricmc.loader.api.FabricLoader;
 import net.minecraft.SharedConstants;
 import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.network.ClientPlayerEntity;
 import net.minecraft.client.toast.SystemToast;
 import net.minecraft.client.toast.ToastManager;
 import net.minecraft.resource.metadata.PackResourceMetadataReader;
+import net.minecraft.text.ClickEvent;
+import net.minecraft.text.HoverEvent;
+import net.minecraft.text.Style;
 import net.minecraft.text.Text;
+import net.minecraft.util.Formatting;
 import net.minecraft.util.JsonHelper;
 
 public class FabricDynamicMod extends DynamicPackModBase implements ClientModInitializer {
-    private static final boolean SHOW_STATE = false;
     private SystemToast toast = null;
     private long toastUpdated = 0;
 
@@ -40,6 +47,37 @@ public void setToastContent(Text title, Text text) {
     public void onInitializeClient() {
         var gameDir = FabricLoader.getInstance().getGameDir().toFile();
         init(gameDir);
+
+        ClientPlayConnectionEvents.JOIN.register((handler, sender, client) -> {
+            ClientPlayerEntity player = client.player;
+            Text download = Text.translatable("dynamicpack.status_checker.download")
+                    .fillStyle(Style.EMPTY
+                            .withHoverEvent(new HoverEvent(HoverEvent.Action.SHOW_TEXT, Text.translatable("dynamicpack.status_checker.download.hover", Text.literal(Mod.MODRINTH_URL).formatted(Formatting.UNDERLINE, Formatting.AQUA))))
+                            .withClickEvent(new ClickEvent(ClickEvent.Action.OPEN_URL, Mod.MODRINTH_URL))
+                    )
+                    .formatted(Formatting.YELLOW, Formatting.UNDERLINE);
+
+
+            if (player == null) {
+                Out.warn("player == null on world join");
+
+            } else if (!StatusChecker.isSafe()) {
+                player.sendMessage(Text.translatable("dynamicpack.status_checker.not_safe", download));
+                setToastContent(Text.translatable("dynamicpack.status_checker.not_safe.toast.title"),
+                        Text.translatable("dynamicpack.status_checker.not_safe.toast.description"));
+
+            } else if (!StatusChecker.isFormatActual()) {
+                player.sendMessage(Text.translatable("dynamicpack.status_checker.format_not_actual", download));
+
+            } else if (StatusChecker.isModUpdateAvailable()) {
+                Out.println("DynamicPack mod update available: " + Mod.MODRINTH_URL);
+
+            } else if (!StatusChecker.isChecked()) {
+                Out.warn("StatusChecker isChecked = false :(");
+            } else {
+                Out.println("Mod in actual state in current date!");
+            }
+        });
     }
 
     @Override
diff --git a/src/main/resources/assets/dynamicpack/lang/en_us.json b/src/main/resources/assets/dynamicpack/lang/en_us.json
index 042f466..dda5f11 100644
--- a/src/main/resources/assets/dynamicpack/lang/en_us.json
+++ b/src/main/resources/assets/dynamicpack/lang/en_us.json
@@ -15,5 +15,11 @@
   "dynamicpack.toast.pack.state.unknown.description": "Processing...",
   "dynamicpack.screen.pack.description": "This resource pack support DynamicPack features!",
   "dynamicpack.screen.pack.remote_type": "Remote type: %s",
-  "dynamicpack.screen.pack.latestUpdated": "Latest updated at: %s"
+  "dynamicpack.screen.pack.latestUpdated": "Latest updated at: %s",
+  "dynamicpack.status_checker.not_safe": "Security update available for DynamicPack mod! This message should not be ignored, since the update has fixed possible vulnerabilities: %s",
+  "dynamicpack.status_checker.not_safe.toast.title": "DynamicPack",
+  "dynamicpack.status_checker.not_safe.toast.description": "Security update available",
+  "dynamicpack.status_checker.format_not_actual": "Dynamic pack format update available! Perhaps resource pack developers will use it, and then without updating the mod they will stop working: %s",
+  "dynamicpack.status_checker.download": "Download!",
+  "dynamicpack.status_checker.download.hover": "Click for go to %s"
 }
\ No newline at end of file
diff --git a/src/main/resources/assets/dynamicpack/lang/ru_ru.json b/src/main/resources/assets/dynamicpack/lang/ru_ru.json
index 0f4e7cd..686aaac 100644
--- a/src/main/resources/assets/dynamicpack/lang/ru_ru.json
+++ b/src/main/resources/assets/dynamicpack/lang/ru_ru.json
@@ -15,5 +15,11 @@
   "dynamicpack.toast.pack.state.unknown.description": "Обработка...",
   "dynamicpack.screen.pack.description": "Этот ресурспак поддерживает возможности мода DynamicPack!",
   "dynamicpack.screen.pack.remote_type": "Тип: %s",
-  "dynamicpack.screen.pack.latestUpdated": "Обновлён: %s"
+  "dynamicpack.screen.pack.latestUpdated": "Обновлён: %s",
+  "dynamicpack.status_checker.not_safe": "Доступно обновление безопасности для мода DynamicPack! Это сообщение не стоит игнорировать, поскольку в обновлении были исправлены возможные уязвимости: %s",
+  "dynamicpack.status_checker.not_safe.toast.title": "DynamicPack",
+  "dynamicpack.status_checker.not_safe.toast.description": "Доступно обновление безопасности",
+  "dynamicpack.status_checker.format_not_actual": "Доступно обновление формата динамических паков! Возможно разработчики ресурспаков будут его использовать, и тогда без обновления мода они работать перестанут: %s",
+  "dynamicpack.status_checker.download": "Загрузить!",
+  "dynamicpack.status_checker.download.hover": "Нажмите чтобы перейти %s"
 }
\ No newline at end of file