diff --git a/server/gameserver/room.cc b/server/gameserver/room.cc
index 06f1e1b9..b39440c6 100644
--- a/server/gameserver/room.cc
+++ b/server/gameserver/room.cc
@@ -1195,6 +1195,11 @@ void Room::TraverseHumanList(std::function<bool (Human*)> func)
 void Room::TraverseAliveHumanList(std::function<bool (Human*)> func)
 {
     for (auto& pair : alive_human_hash_) {
+#ifdef MYDEBUG
+        if (pair.second->IsOb()) {
+            abort();
+        }
+#endif
         if (pair.second) {
             if (!func(pair.second)) {
                 break;
@@ -1217,6 +1222,11 @@ void Room::TraverseEntityList(std::function<bool (Entity*)> func)
 void Room::TraverseAlivePlayers(std::function<bool (Human*)> func)
 {
     for (auto& pair : alive_player_hash_) {
+#ifdef MYDEBUG
+        if (pair.second->IsOb()) {
+            abort();
+        }
+#endif
         if (!func(pair.second)) {
             break;
         }
@@ -2504,6 +2514,11 @@ void Room::AddToHumanHash(Human* hum)
 
 void Room::AddToAliveHumanHash(Human* hum)
 {
+#ifdef MYDEBUG
+    if (hum->IsOb()) {
+        abort();
+    }
+#endif
     alive_human_hash_[hum->GetUniId()] = hum;
     if (hum->IsPlayer()) {
         alive_player_hash_[hum->GetUniId()] = hum;