diff --git a/server/gameserver/incubator.h b/server/gameserver/incubator.h
index 0cc9b9b..95359bf 100644
--- a/server/gameserver/incubator.h
+++ b/server/gameserver/incubator.h
@@ -9,7 +9,8 @@ class Incubator
 
     void Init();
     void UnInit();
+    void AddHoldHuman(Human* num);
 
 private:
-    std::list<Human*> hold_humans_;
+    std::set<Human*> hold_humans_;
 };