Core/Spells: defined unknown field in spell start and spell go packet struct

src/server/game/Server/Packets/SpellPackets.cpp

@@ -117,7 +117,7 @@ ByteBuffer& operator<<(ByteBuffer& data, WorldPackets::Spells::SpellCastData con
     data << uint8(spellCastData.CastID);
     data << uint32(spellCastData.SpellID);
     data << uint32(spellCastData.CastFlags);
-    data << uint32(0); // m_timer Todo: research
+    data << uint32(spellCastData.CastFlagsEx);
     data << uint32(spellCastData.CastTime);
 
     if (spellCastData.HitInfo)

src/server/game/Server/Packets/SpellPackets.h

@@ -104,6 +104,7 @@ namespace WorldPackets
             uint8 CastID = 0;
             uint32 SpellID = 0;
             uint32 CastFlags = 0;
+            uint32 CastFlagsEx = 0;
             uint32 CastTime = 0;
             SpellTargetData Target;
             Optional<SpellHitInfo> HitInfo;

src/server/game/Spells/Spell.cpp

@@ -550,6 +550,7 @@ m_caster((info->HasAttribute(SPELL_ATTR6_CAST_BY_CHARMER) && caster->GetCharmerO
     m_comboPointGain = 0;
     m_delayStart = 0;
     m_delayAtDamageCount = 0;
+    m_castFlagsEx = 0;
 
     m_applyMultiplierMask = 0;
     m_auraScaleMask = 0;
@@ -4178,6 +4179,7 @@ void Spell::SendSpellStart()
     castData.CastID = m_cast_count;
     castData.SpellID = m_spellInfo->Id;
     castData.CastFlags = castFlags;
+    castData.CastFlagsEx = m_castFlagsEx;
     castData.CastTime = m_casttime;
 
     //data << uint32(m_timer);                                // delay?
@@ -4304,6 +4306,7 @@ void Spell::SendSpellGo()
     castData.CastID = m_cast_count;
     castData.SpellID = m_spellInfo->Id;
     castData.CastFlags = castFlags;
+    castData.CastFlagsEx = m_castFlagsEx;
     castData.CastTime = GameTime::GetGameTimeMS();
 
     castData.HitInfo = boost::in_place();

src/server/game/Spells/Spell.h

@@ -520,6 +520,7 @@ class TC_GAME_API Spell
         SpellCastTargets m_targets;
         int8 m_comboPointGain;
         SpellCustomErrors m_customError;
+        uint32 m_castFlagsEx;
 
         UsedSpellMods m_appliedMods;