diff --git a/src/main/kotlin/com/github/rushyverse/api/gui/GUI.kt b/src/main/kotlin/com/github/rushyverse/api/gui/GUI.kt
index ad0f2f63..fb354055 100644
--- a/src/main/kotlin/com/github/rushyverse/api/gui/GUI.kt
+++ b/src/main/kotlin/com/github/rushyverse/api/gui/GUI.kt
@@ -288,7 +288,7 @@ public abstract class GUI<T>(
      * @param key Key to create the inventory for.
      * @return New created inventory.
      */
-    protected abstract fun createInventory(key: T): Inventory
+    protected abstract suspend fun createInventory(key: T): Inventory
 
     /**
      * Create a new flow of [Item][ItemStack] to fill the inventory with.
diff --git a/src/main/kotlin/com/github/rushyverse/api/gui/PlayerGUI.kt b/src/main/kotlin/com/github/rushyverse/api/gui/PlayerGUI.kt
index c94ca7ae..d0238193 100644
--- a/src/main/kotlin/com/github/rushyverse/api/gui/PlayerGUI.kt
+++ b/src/main/kotlin/com/github/rushyverse/api/gui/PlayerGUI.kt
@@ -42,7 +42,7 @@ public abstract class PlayerGUI(
      * @param key The client to create the inventory for.
      * @return The inventory for the client.
      */
-    override fun createInventory(key: Client): Inventory {
+    override suspend fun createInventory(key: Client): Inventory {
         val player = key.requirePlayer()
         return createInventory(player, key)
     }
@@ -54,7 +54,7 @@ public abstract class PlayerGUI(
      * @param client The client to create the inventory for.
      * @return The inventory for the client.
      */
-    protected abstract fun createInventory(owner: InventoryHolder, client: Client): Inventory
+    protected abstract suspend fun createInventory(owner: InventoryHolder, client: Client): Inventory
 
     override suspend fun closeClient(client: Client, closeInventory: Boolean): Boolean {
         val (inventory, job) = mutex.withLock { inventories.remove(client) } ?: return false
diff --git a/src/main/kotlin/com/github/rushyverse/api/gui/SingleGUI.kt b/src/main/kotlin/com/github/rushyverse/api/gui/SingleGUI.kt
index ba9a2817..47b5ae5e 100644
--- a/src/main/kotlin/com/github/rushyverse/api/gui/SingleGUI.kt
+++ b/src/main/kotlin/com/github/rushyverse/api/gui/SingleGUI.kt
@@ -44,7 +44,7 @@ public abstract class SingleGUI(
         return scope + SupervisorJob(scope.coroutineContext.job)
     }
 
-    override fun createInventory(key: Unit): Inventory {
+    override suspend fun createInventory(key: Unit): Inventory {
         return createInventory()
     }
 
@@ -52,7 +52,7 @@ public abstract class SingleGUI(
      * Create the inventory.
      * @return New created inventory.
      */
-    protected abstract fun createInventory(): Inventory
+    protected abstract suspend fun createInventory(): Inventory
 
     /**
      * Update the inventory.
diff --git a/src/test/kotlin/com/github/rushyverse/api/gui/LocalePlayerGUITest.kt b/src/test/kotlin/com/github/rushyverse/api/gui/LocalePlayerGUITest.kt
index 940d583e..4249e861 100644
--- a/src/test/kotlin/com/github/rushyverse/api/gui/LocalePlayerGUITest.kt
+++ b/src/test/kotlin/com/github/rushyverse/api/gui/LocalePlayerGUITest.kt
@@ -206,7 +206,7 @@ private abstract class AbstractLocaleGUITest(
     animation: InventoryLoadingAnimation<Locale>? = null
 ) : LocaleGUI(plugin, animation) {
 
-    override fun createInventory(key: Locale): Inventory {
+    override suspend fun createInventory(key: Locale): Inventory {
         return serverMock.createInventory(null, type)
     }
 
diff --git a/src/test/kotlin/com/github/rushyverse/api/gui/PlayerGUITest.kt b/src/test/kotlin/com/github/rushyverse/api/gui/PlayerGUITest.kt
index 5213edae..3672cda5 100644
--- a/src/test/kotlin/com/github/rushyverse/api/gui/PlayerGUITest.kt
+++ b/src/test/kotlin/com/github/rushyverse/api/gui/PlayerGUITest.kt
@@ -174,7 +174,7 @@ private abstract class AbstractPlayerGUITest(
     loadingAnimation: InventoryLoadingAnimation<Client>? = null
 ) : PlayerGUI(loadingAnimation) {
 
-    override fun createInventory(owner: InventoryHolder, client: Client): Inventory {
+    override suspend fun createInventory(owner: InventoryHolder, client: Client): Inventory {
         return serverMock.createInventory(owner, type)
     }
 
diff --git a/src/test/kotlin/com/github/rushyverse/api/gui/SingleGUITest.kt b/src/test/kotlin/com/github/rushyverse/api/gui/SingleGUITest.kt
index 38634edd..51601e76 100644
--- a/src/test/kotlin/com/github/rushyverse/api/gui/SingleGUITest.kt
+++ b/src/test/kotlin/com/github/rushyverse/api/gui/SingleGUITest.kt
@@ -192,7 +192,7 @@ private abstract class AbstractSingleGUITest(
     animation: InventoryLoadingAnimation<Unit>? = null
 ) : SingleGUI(plugin, animation) {
 
-    override fun createInventory(): Inventory {
+    override suspend fun createInventory(): Inventory {
         return serverMock.createInventory(null, type)
     }