diff --git a/src/main/kotlin/xyz/fortern/forternhelper/Helper.kt b/src/main/kotlin/xyz/fortern/forternhelper/Helper.kt
index ced2b9a..1948589 100644
--- a/src/main/kotlin/xyz/fortern/forternhelper/Helper.kt
+++ b/src/main/kotlin/xyz/fortern/forternhelper/Helper.kt
@@ -4,24 +4,33 @@ import me.clip.placeholderapi.expansion.PlaceholderExpansion
 import net.kyori.adventure.platform.bukkit.BukkitAudiences
 import org.bukkit.Bukkit
 import org.bukkit.plugin.java.JavaPlugin
+import xyz.fortern.forternhelper.async.AsyncManager
 import xyz.fortern.forternhelper.command.HelperCommand
 import xyz.fortern.forternhelper.listener.ForternListener
 import xyz.fortern.forternhelper.placeholder.ForternExpansion
+import java.io.File
 
 class Helper : JavaPlugin() {
     private lateinit var adventure: BukkitAudiences
 
     private lateinit var expansion: PlaceholderExpansion
 
+    private lateinit var asyncManager: AsyncManager
+
     override fun onEnable() {
         // Plugin startup logic
         this.adventure = BukkitAudiences.create(this)
-        logger.info("Registering listeners...")
+
+        // register asyncManager
+        logger.info("Registering asyncManager...")
+        asyncManager = AsyncManager(this)
+
         // register listeners
+        logger.info("Registering listeners...")
         Bukkit.getPluginManager().registerEvents(ForternListener(this), this)
-        logger.info("Registering commands...")
         // register commands
-        Bukkit.getPluginCommand("helper")?.setExecutor(HelperCommand(this, adventure))
+        logger.info("Registering commands...")
+        Bukkit.getPluginCommand("helper")!!.setExecutor(HelperCommand(this, adventure, asyncManager))
         // register placeholders
         if (Bukkit.getPluginManager().isPluginEnabled("PlaceholderAPI")) {
             expansion = ForternExpansion(this)
diff --git a/src/main/kotlin/xyz/fortern/forternhelper/async/AsyncManager.kt b/src/main/kotlin/xyz/fortern/forternhelper/async/AsyncManager.kt
new file mode 100644
index 0000000..d70bb76
--- /dev/null
+++ b/src/main/kotlin/xyz/fortern/forternhelper/async/AsyncManager.kt
@@ -0,0 +1,88 @@
+package xyz.fortern.forternhelper.async
+
+import org.bukkit.Bukkit
+import org.bukkit.plugin.java.JavaPlugin
+import java.util.concurrent.CompletableFuture
+import java.util.logging.Level
+
+class AsyncManager(
+    private val plugin: JavaPlugin,
+) {
+    private val tasks: MutableSet<AsyncTask> = HashSet()
+
+    init {
+        // sync
+        Bukkit.getScheduler().runTaskTimer(plugin, Runnable {
+            val iterator = tasks.iterator()
+            while (iterator.hasNext()) {
+                val asyncTaskTracker = iterator.next()
+                try {
+                    val result = asyncTaskTracker.tick()
+                    if (result == AsyncTask.Result.RUNNING) {
+                        continue
+                    } else if (result == AsyncTask.Result.TIMEOUT) {
+                        plugin.logger.warning("Async task timed out: ${asyncTaskTracker.info}")
+                    }
+                } catch (t: Throwable) {
+                    plugin.logger.log(Level.SEVERE, "Error while ticking AsyncManager", t)
+                }
+                iterator.remove()
+            }
+        }, 0, 0)
+    }
+
+    /**
+     * 添加一个异步任务[asyncFun]，该异步任务结束后，会在主线程同步执行另一个任务[syncFun]。
+     * 需要超时时间[timeout]。
+     * 此方法应当在主线程调用。
+     */
+    fun execInMainAfterAsync(info: String, timeout: Int, asyncFun: () -> Unit, syncFun: () -> Unit) {
+        val future = CompletableFuture<Void>()
+        val bukkitTask = Bukkit.getScheduler().runTaskAsynchronously(plugin, Runnable {
+            try {
+                asyncFun()
+                future.complete(null)
+            } catch (t: Throwable) {
+                future.completeExceptionally(t)
+            }
+        })
+        val asyncTaskTracker = AsyncTask(bukkitTask.taskId, info, future, timeout, syncFun)
+        tasks.add(asyncTaskTracker)
+    }
+}
+
+class AsyncTask(
+    val id: Int,
+    val info: String,
+    val future: CompletableFuture<Void>,
+    var timeout: Int,
+    val syncFun: () -> Unit,
+) {
+    /**
+     * 每tick执行一次。 返回 [Result.TIMEOUT] 如果超时; 返回 [Result.TIMEOUT] 如果正在运行; 返回 [Result.DONE] 如果完成。
+     *
+     * @throws Throwable 当异步任务或同步任务执行出现异常时，抛出那个异常
+     */
+    @Throws(Throwable::class)
+    fun tick(): Result {
+        if (future.isDone) {
+            if (!future.isCompletedExceptionally) {
+                syncFun.invoke()
+            } else {
+                throw future.exceptionNow()
+            }
+            return Result.DONE
+        }
+        timeout--
+        if (timeout < 0) {
+            future.cancel(true)
+            return Result.TIMEOUT
+        }
+        return Result.RUNNING
+    }
+
+    enum class Result {
+        RUNNING, DONE, TIMEOUT
+    }
+}
+
diff --git a/src/main/kotlin/xyz/fortern/forternhelper/command/HelperCommand.kt b/src/main/kotlin/xyz/fortern/forternhelper/command/HelperCommand.kt
index e4e7474..f39c893 100644
--- a/src/main/kotlin/xyz/fortern/forternhelper/command/HelperCommand.kt
+++ b/src/main/kotlin/xyz/fortern/forternhelper/command/HelperCommand.kt
@@ -1,7 +1,5 @@
 package xyz.fortern.forternhelper.command
 
-import de.tr7zw.nbtapi.NBT
-import de.tr7zw.nbtapi.iface.ReadWriteNBT
 import net.kyori.adventure.platform.bukkit.BukkitAudiences
 import net.kyori.adventure.text.Component
 import net.kyori.adventure.text.format.NamedTextColor
@@ -11,14 +9,13 @@ import org.bukkit.command.CommandSender
 import org.bukkit.command.TabExecutor
 import org.bukkit.entity.Player
 import org.bukkit.plugin.java.JavaPlugin
-import java.io.File
-import java.io.FileReader
+import xyz.fortern.forternhelper.async.AsyncManager
 
 class HelperCommand(
     private val plugin: JavaPlugin,
     private val adventure: BukkitAudiences,
-
-    ) : TabExecutor {
+    private val asyncManager: AsyncManager,
+) : TabExecutor {
     private val subCommands: List<String> = listOf("loadlevel")
     private val helpMessages = listOf(
         Component.text("fortern-helper v${plugin.description.version}", NamedTextColor.GREEN),
@@ -66,16 +63,6 @@ class HelperCommand(
                 onLoadLevel(sender, args, exe)
             }
 
-            "setblock" -> {
-                setBlockFromNbt(sender, args, exe)
-                null
-            }
-
-            "getitem" -> {
-                getItemFromNbt(sender, args, exe)
-                null
-            }
-
             else -> {
                 if (exe) {
                     adventure.sender(sender).sendMessage(Component.text("错误的子命令"))
@@ -88,54 +75,6 @@ class HelperCommand(
         }
     }
 
-    private fun getItemFromNbt(sender: CommandSender, args: List<String>, exe: Boolean) {
-        // args[0]:getitem | args[1]:0 | args[2]:txt
-        if (!exe) return
-        if (sender !is Player) return
-        if (!sender.isOp) return
-        if (args.size < 2) return
-        val i = args[1]
-        val isNbt = if (args.size > 2) args[2] == "nbt" else false
-        val itemNbtDir = File(plugin.dataFolder, "item-nbt")
-        val nbt = if (isNbt) {
-            val file = File(itemNbtDir, "${i}.nbt")
-            if (!file.exists()) return
-            NBT.readFile(file)
-        } else {
-            val file = File(itemNbtDir, "${i}.txt")
-            if (!file.exists()) return
-            NBT.parseNBT(FileReader(file).readAllAsString())
-        }
-        sender.inventory.addItem(NBT.itemStackFromNBT(nbt))
-        return
-    }
-
-    private fun setBlockFromNbt(sender: CommandSender, args: List<String>, exe: Boolean) {
-        // args[0]:setblock | args[1]:0 | args[2]:txt
-        if (!exe) return
-        if (sender !is Player) return
-        if (!sender.isOp) return
-        if (args.size < 2) return
-        val i = args[1]
-        val isNbt = if (args.size > 2) args[2] == "nbt" else false
-        val world = sender.world
-        val blockState = world.getBlockState(0, 128, 0)
-        val itemNbtDir = File(plugin.dataFolder, "block-nbt")
-        val readWriteNBT = if (isNbt) {
-            val file = File(itemNbtDir, "${i}.nbt")
-            if (!file.exists()) return
-            NBT.readFile(file)
-        } else {
-            val file = File(itemNbtDir, "${i}.txt")
-            if (!file.exists()) return
-            NBT.parseNBT(FileReader(file).readAllAsString())
-        }
-        NBT.modify(blockState) { nbt: ReadWriteNBT ->
-            nbt.mergeCompound(readWriteNBT)
-        }
-        return
-    }
-
     private fun onHelp(sender: CommandSender, exe: Boolean): List<String>? {
         if (exe) sendHelp(sender)
         return null