diff --git a/src/game/char.cpp b/src/game/char.cpp
index 4d73434..1b3dbfa 100644
--- a/src/game/char.cpp
+++ b/src/game/char.cpp
@@ -6010,13 +6010,13 @@ void CHARACTER::EffectPacket(int enumEffectType)
 	PacketAround(&p, sizeof(TPacketGCSpecialEffect));
 }
 
-void CHARACTER::SpecificEffectPacket(const char filename[MAX_EFFECT_FILE_NAME])
+void CHARACTER::SpecificEffectPacket(const std::string& stEffectName)
 {
 	TPacketGCSpecificEffect p;
 
 	p.header = HEADER_GC_SPECIFIC_EFFECT;
 	p.vid = GetVID();
-	memcpy (p.effect_file, filename, MAX_EFFECT_FILE_NAME);
+	strlcpy(p.effect_file, stEffectName.c_str(), sizeof(p.effect_file));
 
 	PacketAround(&p, sizeof(TPacketGCSpecificEffect));
 }
diff --git a/src/game/char.h b/src/game/char.h
index 8d52d56..6779b3a 100644
--- a/src/game/char.h
+++ b/src/game/char.h
@@ -1091,7 +1091,7 @@ class CHARACTER : public CEntity, public CFSM, public CHorseRider
 
 		//	void			PotionPacket(int iPotionType);
 		void			EffectPacket(int enumEffectType);
-		void			SpecificEffectPacket(const char filename[128]);
+		void			SpecificEffectPacket(const std::string& stEffectName);
 
 		// ADD_MONSTER_REFINE
 		bool			DoRefine(LPITEM item, bool bMoneyOnly = false);
diff --git a/src/game/char_battle.cpp b/src/game/char_battle.cpp
index 3817eac..d962cff 100644
--- a/src/game/char_battle.cpp
+++ b/src/game/char_battle.cpp
@@ -3195,7 +3195,7 @@ LPCHARACTER CHARACTER::GetNearestVictim(LPCHARACTER pkChr)
 
 		LPCHARACTER pAttacker = CHARACTER_MANAGER::instance().Find(c_VID);
 
-		if (!pAttacker)
+		if (!pAttacker || pAttacker->IsDead())
 			continue;
 
 		if (pAttacker->IsAffectFlag(AFF_EUNHYUNG) || 
diff --git a/src/game/cmd_gm.cpp b/src/game/cmd_gm.cpp
index 28c13e6..1efb680 100644
--- a/src/game/cmd_gm.cpp
+++ b/src/game/cmd_gm.cpp
@@ -4082,28 +4082,28 @@ ACMD (do_item_full_set)
 		{
 			
 			item = ITEM_MANAGER::instance().CreateItem(11699);
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(13049);
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(15189 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(189 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(12529 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(14109 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(17209 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(16209 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 		}
 		break;
@@ -4111,28 +4111,28 @@ ACMD (do_item_full_set)
 		{
 			
 			item = ITEM_MANAGER::instance().CreateItem(11299);
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(13049);
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(15189 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(3159 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(12249 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(14109 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(17109 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(16109 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 		}
 		break;
@@ -4140,28 +4140,28 @@ ACMD (do_item_full_set)
 		{
 			
 			item = ITEM_MANAGER::instance().CreateItem(11899);
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(13049);
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(15189 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(7159 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(12669 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(14109 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(17209 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(16209 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 		}
 		break;
@@ -4169,31 +4169,35 @@ ACMD (do_item_full_set)
 		{
 			
 			item = ITEM_MANAGER::instance().CreateItem(11499);
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(13049);
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(15189 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(1139 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(12389 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(14109 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(17189 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 			item = ITEM_MANAGER::instance().CreateItem(16189 );
-			if (!item || !item->EquipTo(ch, item->FindEquipCell(ch)))
+			if (item && !item->EquipTo(ch, item->FindEquipCell(ch)))
 				M2_DESTROY_ITEM(item);
 		}
 		break;
+
+	default:
+		ch->ChatPacket(CHAT_TYPE_INFO, "Full set is not available for your job");
+		break;
 	}
 }
 
diff --git a/src/game/desc.cpp b/src/game/desc.cpp
index 9c281b4..0016c57 100644
--- a/src/game/desc.cpp
+++ b/src/game/desc.cpp
@@ -428,6 +428,13 @@ void DESC::Packet(const void * c_pvData, int iSize)
 	if (m_iPhase == PHASE_CLOSE) // 끊는 상태면 보내지 않는다.
 		return;
 
+	if (!m_lpOutputBuffer)
+	{
+		sys_err("DESC::Packet: Trying to send packet but output buffer is NULL! (DESC: %p)", this);
+		SetPhase(PHASE_CLOSE);
+		return;
+	}
+
 	if (m_stRelayName.length() != 0)
 	{
 		// Relay 패킷은 암호화하지 않는다.
diff --git a/src/game/guild.cpp b/src/game/guild.cpp
index 1e1a771..9e7ce59 100644
--- a/src/game/guild.cpp
+++ b/src/game/guild.cpp
@@ -2013,13 +2013,13 @@ void CGuild::Invite( LPCHARACTER pchInviter, LPCHARACTER pchInvitee )
 
 	TPacketGCGuild p;
 	p.header	= HEADER_GC_GUILD;
-	p.size	= sizeof(p) + sizeof(DWORD) + GUILD_NAME_MAX_LEN + 1;
+	p.size	= sizeof(p) + sizeof(DWORD) + GUILD_NAME_MAX_LEN;
 	p.subheader	= GUILD_SUBHEADER_GC_GUILD_INVITE;
 
 	TEMP_BUFFER buf;
 	buf.write( &p, sizeof(p) );
 	buf.write( &gid, sizeof(DWORD) );
-	buf.write( GetName(), GUILD_NAME_MAX_LEN + 1 );
+	buf.write( GetName(), GUILD_NAME_MAX_LEN );
 
 	pchInvitee->GetDesc()->Packet( buf.read_peek(), buf.size() );
 }
diff --git a/src/game/item_manager.cpp b/src/game/item_manager.cpp
index 489ece7..585c13f 100644
--- a/src/game/item_manager.cpp
+++ b/src/game/item_manager.cpp
@@ -469,21 +469,31 @@ void ITEM_MANAGER::SaveSingleItem(LPITEM item)
 
 void ITEM_MANAGER::Update()
 {
-	std::unordered_set<LPITEM>::iterator it = m_set_pkItemForDelayedSave.begin();
-	std::unordered_set<LPITEM>::iterator this_it;
-
-	while (it != m_set_pkItemForDelayedSave.end())
+	for (auto it = m_set_pkItemForDelayedSave.begin(); it != m_set_pkItemForDelayedSave.end();)
 	{
-		this_it = it++;
-		LPITEM item = *this_it;
-
-		// SLOW_QUERY 플래그가 있는 것은 종료시에만 저장한다.
-		if (item->GetOwner() && IS_SET(item->GetFlag(), ITEM_FLAG_SLOW_QUERY))
+		LPITEM item = *it;
+		if (!item)
+		{
+			sys_err("nullptr item, erasing from delayed save.");
+			it = m_set_pkItemForDelayedSave.erase(it);
 			continue;
+		}
+
+		if (!FindByVID(item->GetVID()))
+		{
+			sys_err("Invalid item(%u), erasing from delayed save.", item->GetVID());
+			it = m_set_pkItemForDelayedSave.erase(it);
+			continue;
+		}
+
+		if (item->GetOwner() && IS_SET(item->GetFlag(), ITEM_FLAG_SLOW_QUERY))
+		{
+			++it; // just skip don't erase
+			continue;
+		}
 
 		SaveSingleItem(item);
-
-		m_set_pkItemForDelayedSave.erase(this_it);
+		it = m_set_pkItemForDelayedSave.erase(it);
 	}
 }
 
@@ -619,28 +629,29 @@ TItemTable * ITEM_MANAGER::GetTable(DWORD vnum)
 
 int ITEM_MANAGER::RealNumber(DWORD vnum)
 {
-	int bot, top, mid;
+	if (m_vec_prototype.empty())
+		return -1;
 
-	bot = 0;
-	top = m_vec_prototype.size();
+	int left = 0;
+	int right = m_vec_prototype.size() - 1;
 
-	TItemTable * pTable = &m_vec_prototype[0];
-
-	while (1)
+	while (left <= right)
 	{
-		mid = (bot + top) >> 1;
+		int mid = (left + right) / 2;
 
-		if ((pTable + mid)->dwVnum == vnum)
-			return (mid);
+		if (mid < 0 || mid >= static_cast<int>(m_vec_prototype.size()))
+			return -1;
 
-		if (bot >= top)
-			return (-1);
+		if (m_vec_prototype[mid].dwVnum == vnum)
+			return mid;
 
-		if ((pTable + mid)->dwVnum > vnum)
-			top = mid - 1;
-		else        
-			bot = mid + 1;
+		if (m_vec_prototype[mid].dwVnum > vnum)
+			right = mid - 1;
+		else
+			left = mid + 1;
 	}
+
+	return -1;
 }
 
 bool ITEM_MANAGER::GetVnum(const char * c_pszName, DWORD & r_dwVnum)