Core/Units: Power handling improvements

* Don't include creature_template power multipliers in CreateMana updatefield
* Allow NPCs to have power types other than mana
* Add missing Essence config regeneration rate
* Fixed demon hunter powers not decaying immediately after combat
* Fixed some powers decaying immediately out of combat after energizing (for example holy power)
* Replace hardcoded list of powers to set to full on levelup with a db2 flag check
* Updated Creature::GetPowerIndex for 10.1 new power types

17 files changed, 128 insertions, 73 deletions

diff --git a/src/server/game/DataStores/DB2Stores.h b/src/server/game/DataStores/DB2Stores.h
index c508a02f0b1..f8c07ae3432 100644
--- a/src/server/game/DataStores/DB2Stores.h
+++ b/src/server/game/DataStores/DB2Stores.h
@@ -180,6 +180,7 @@ TC_GAME_API extern DB2Storage<ParagonReputationEntry>               sParagonRepu
 TC_GAME_API extern DB2Storage<PhaseEntry>                           sPhaseStore;
 TC_GAME_API extern DB2Storage<PlayerConditionEntry>                 sPlayerConditionStore;
 TC_GAME_API extern DB2Storage<PowerDisplayEntry>                    sPowerDisplayStore;
+TC_GAME_API extern DB2Storage<PowerTypeEntry>                       sPowerTypeStore;
 TC_GAME_API extern DB2Storage<PvpTalentEntry>                       sPvpTalentStore;
 TC_GAME_API extern DB2Storage<PvpTalentCategoryEntry>               sPvpTalentCategoryStore;
 TC_GAME_API extern DB2Storage<PvpTalentSlotUnlockEntry>             sPvpTalentSlotUnlockStore;
diff --git a/src/server/game/DataStores/DBCEnums.h b/src/server/game/DataStores/DBCEnums.h
index 637537bf35e..bd8ee99f2be 100644
--- a/src/server/game/DataStores/DBCEnums.h
+++ b/src/server/game/DataStores/DBCEnums.h
@@ -1666,18 +1666,18 @@ enum class PlayerInteractionType : int32
 
 enum class PowerTypeFlags : int16
 {
-    StopRegenWhileCasting         = 0x0001,
+    StopRegenWhileCasting         = 0x0001, // NYI
     UseRegenInterrupt             = 0x0002,
-    FillFractionalPowerOnEnergize = 0x0008,
-    NoClientPrediction            = 0x0010,
+    FillFractionalPowerOnEnergize = 0x0008, // NYI
+    NoClientPrediction            = 0x0010, // NYI
     UnitsUseDefaultPowerOnInit    = 0x0020,
-    NotSetToDefaultOnResurrect    = 0x0040,
+    NotSetToDefaultOnResurrect    = 0x0040, // NYI
     IsUsedByNPCs                  = 0x0080,
-    ContinueRegenWhileFatigued    = 0x0200,
-    RegenAffectedByHaste          = 0x0400,
+    ContinueRegenWhileFatigued    = 0x0200, // NYI
+    RegenAffectedByHaste          = 0x0400, // NYI
     SetToMaxOnLevelUp             = 0x1000,
-    SetToMaxLevelOnInitialLogIn   = 0x2000,
-    AllowCostModsForPlayers       = 0x4000
+    SetToMaxLevelOnInitialLogIn   = 0x2000, // NYI
+    AllowCostModsForPlayers       = 0x4000  // NYI
 };
 
 DEFINE_ENUM_FLAG(PowerTypeFlags);
diff --git a/src/server/game/Entities/Creature/Creature.cpp b/src/server/game/Entities/Creature/Creature.cpp
index d41b0162613..a2f56b7daf2 100644
--- a/src/server/game/Entities/Creature/Creature.cpp
+++ b/src/server/game/Entities/Creature/Creature.cpp
@@ -1563,23 +1563,22 @@ void Creature::UpdateLevelDependantStats()
     SetHealth(health);
     ResetPlayerDamageReq();
 
+    SetStatFlatModifier(UNIT_MOD_HEALTH, BASE_VALUE, (float)health);
+
     // mana
-    uint32 mana = stats->GenerateMana(cInfo);
-    SetCreateMana(mana);
+    Powers powerType = CalculateDisplayPowerType();
+    SetCreateMana(stats->BaseMana);
+    SetStatPctModifier(UnitMods(UNIT_MOD_POWER_START + AsUnderlyingType(powerType)), BASE_PCT, cInfo->ModMana * cInfo->ModManaExtra);
+    SetPowerType(powerType);
 
-    switch (GetClass())
+    if (PowerTypeEntry const* powerTypeEntry = sDB2Manager.GetPowerTypeEntry(powerType))
     {
-        case CLASS_PALADIN:
-        case CLASS_MAGE:
-            SetMaxPower(POWER_MANA, mana);
-            SetFullPower(POWER_MANA);
-            break;
-        default: // We don't set max power here, 0 makes power bar hidden
-            break;
+        if (powerTypeEntry->GetFlags().HasFlag(PowerTypeFlags::UnitsUseDefaultPowerOnInit))
+            SetPower(powerType, powerTypeEntry->DefaultPower);
+        else
+            SetFullPower(powerType);
     }
 
-    SetStatFlatModifier(UNIT_MOD_HEALTH, BASE_VALUE, (float)health);
-
     // damage
     float basedamage = GetBaseDamageForLevel(level);
 
@@ -1598,7 +1597,7 @@ void Creature::UpdateLevelDependantStats()
     SetStatFlatModifier(UNIT_MOD_ATTACK_POWER, BASE_VALUE, stats->AttackPower);
     SetStatFlatModifier(UNIT_MOD_ATTACK_POWER_RANGED, BASE_VALUE, stats->RangedAttackPower);
 
-    float armor = GetBaseArmorForLevel(level); /// @todo Why is this treated as uint32 when it's a float?
+    float armor = GetBaseArmorForLevel(level);
     SetStatFlatModifier(UNIT_MOD_ARMOR, BASE_VALUE, armor);
 }
 
diff --git a/src/server/game/Entities/Creature/Creature.h b/src/server/game/Entities/Creature/Creature.h
index 9f1f57904a9..a60701e8f26 100644
--- a/src/server/game/Entities/Creature/Creature.h
+++ b/src/server/game/Entities/Creature/Creature.h
@@ -192,6 +192,7 @@ class TC_GAME_API Creature : public Unit, public GridObject<Creature>, public Ma
 
         bool UpdateEntry(uint32 entry, CreatureData const* data = nullptr, bool updateLevel = true);
 
+        int32 GetCreatePowerValue(Powers power) const override;
         bool UpdateStats(Stats stat) override;
         bool UpdateAllStats() override;
         void UpdateArmor() override;
diff --git a/src/server/game/Entities/Creature/CreatureData.h b/src/server/game/Entities/Creature/CreatureData.h
index 7044ccaf665..010afc75434 100644
--- a/src/server/game/Entities/Creature/CreatureData.h
+++ b/src/server/game/Entities/Creature/CreatureData.h
@@ -616,15 +616,6 @@ struct TC_GAME_API CreatureBaseStats
     uint32 RangedAttackPower;
 
     // Helpers
-    uint32 GenerateMana(CreatureTemplate const* info) const
-    {
-        // Mana can be 0.
-        if (!BaseMana)
-            return 0;
-
-        return uint32(ceil(BaseMana * info->ModMana * info->ModManaExtra));
-    }
-
     static CreatureBaseStats const* GetBaseStats(uint8 level, uint8 unitClass);
 };
 
diff --git a/src/server/game/Entities/Pet/Pet.cpp b/src/server/game/Entities/Pet/Pet.cpp
index e95740ea408..5fc48d978ec 100644
--- a/src/server/game/Entities/Pet/Pet.cpp
+++ b/src/server/game/Entities/Pet/Pet.cpp
@@ -896,6 +896,8 @@ bool Guardian::InitStatsForLevel(uint8 petlevel)
         for (uint8 i = SPELL_SCHOOL_HOLY; i < MAX_SPELL_SCHOOL; ++i)
             SetStatFlatModifier(UnitMods(UNIT_MOD_RESISTANCE_START + i), BASE_VALUE, float(cinfo->resistance[i]));
 
+    Powers powerType = CalculateDisplayPowerType();
+
     // Health, Mana or Power, Armor
     PetLevelInfo const* pInfo = sObjectMgr->GetPetLevelInfo(creature_ID, petlevel);
     if (pInfo)                                      // exist in DB
@@ -903,6 +905,8 @@ bool Guardian::InitStatsForLevel(uint8 petlevel)
         SetCreateHealth(pInfo->health);
         SetCreateMana(pInfo->mana);
 
+        SetStatPctModifier(UnitMods(UNIT_MOD_POWER_START + AsUnderlyingType(powerType)), BASE_PCT, 1.0f);
+
         if (pInfo->armor > 0)
             SetStatFlatModifier(UNIT_MOD_ARMOR, BASE_VALUE, float(pInfo->armor));
 
@@ -916,7 +920,7 @@ bool Guardian::InitStatsForLevel(uint8 petlevel)
         ApplyLevelScaling();
 
         SetCreateHealth(sDB2Manager.EvaluateExpectedStat(ExpectedStatType::CreatureHealth, petlevel, cinfo->GetHealthScalingExpansion(), m_unitData->ContentTuningID, Classes(cinfo->unit_class)) * cinfo->ModHealth * cinfo->ModHealthExtra * _GetHealthMod(cinfo->rank));
-        SetCreateMana(stats->GenerateMana(cinfo));
+        SetCreateMana(stats->BaseMana);
         SetCreateStat(STAT_STRENGTH, 22);
         SetCreateStat(STAT_AGILITY, 22);
         SetCreateStat(STAT_STAMINA, 25);
@@ -924,17 +928,7 @@ bool Guardian::InitStatsForLevel(uint8 petlevel)
     }
 
     // Power
-    if (petType == HUNTER_PET) // Hunter pets have focus
-        SetPowerType(POWER_FOCUS);
-    else if (IsPetGhoul() || IsPetAbomination()) // DK pets have energy
-    {
-        SetPowerType(POWER_ENERGY);
-        SetFullPower(POWER_ENERGY);
-    }
-    else if (IsWarlockPet()) // Warlock pets have energy (since 5.x)
-        SetPowerType(POWER_ENERGY);
-    else
-        SetPowerType(POWER_MANA);
+    SetPowerType(powerType);
 
     // Damage
     SetBonusDamage(0);
diff --git a/src/server/game/Entities/Player/Player.cpp b/src/server/game/Entities/Player/Player.cpp
index 56cce2bf0a4..e346b174147 100644
--- a/src/server/game/Entities/Player/Player.cpp
+++ b/src/server/game/Entities/Player/Player.cpp
@@ -167,7 +167,7 @@ Player::Player(WorldSession* session) : Unit(true), m_sceneMgr(this)
     if (!GetSession()->HasPermission(rbac::RBAC_PERM_CAN_FILTER_WHISPERS))
         SetAcceptWhispers(true);
 
-    m_combatExitTime = 0;
+    m_regenInterruptTimestamp = GameTime::Now();
     m_regenTimer = 0;
     m_regenTimerCount = 0;
     m_foodEmoteTimerCount = 0;
@@ -1780,7 +1780,7 @@ void Player::Regenerate(Powers power)
     float addvalue = 0.0f;
     if (!IsInCombat())
     {
-        if (powerType->RegenInterruptTimeMS && GetMSTimeDiffToNow(m_combatExitTime) < uint32(powerType->RegenInterruptTimeMS))
+        if (powerType->GetFlags().HasFlag(PowerTypeFlags::UseRegenInterrupt) && m_regenInterruptTimestamp + Milliseconds(powerType->RegenInterruptTimeMS) < GameTime::Now())
             return;
 
         addvalue = (powerType->RegenPeace + m_unitData->PowerRegenFlatModifier[powerIndex]) * 0.001f * m_regenTimer;
@@ -1809,6 +1809,13 @@ void Player::Regenerate(Powers power)
         RATE_POWER_ARCANE_CHARGES,
         RATE_POWER_FURY,
         RATE_POWER_PAIN,
+        RATE_POWER_ESSENCE,
+        MAX_RATES, // runes
+        MAX_RATES, // runes
+        MAX_RATES, // runes
+        MAX_RATES, // alternate
+        MAX_RATES, // alternate
+        MAX_RATES, // alternate
     };
 
     if (RatesForPower[power] != MAX_RATES)
@@ -1903,6 +1910,17 @@ void Player::Regenerate(Powers power)
     }
 }
 
+void Player::InterruptPowerRegen(Powers power)
+{
+    uint32 powerIndex = GetPowerIndex(power);
+    if (powerIndex == MAX_POWERS || powerIndex >= MAX_POWERS_PER_CLASS)
+        return;
+
+    m_regenInterruptTimestamp = GameTime::Now();
+    m_powerFraction[powerIndex] = 0.0f;
+    SendDirectMessage(WorldPackets::Combat::InterruptPowerRegen(power).Write());
+}
+
 void Player::RegenerateHealth()
 {
     uint32 curValue = GetHealth();
@@ -2382,7 +2400,9 @@ void Player::GiveLevel(uint8 level)
 
     // Only health and mana are set to maximum.
     SetFullHealth();
-    SetFullPower(POWER_MANA);
+    for (PowerTypeEntry const* powerType : sPowerTypeStore)
+        if (powerType->GetFlags().HasFlag(PowerTypeFlags::SetToMaxOnLevelUp))
+            SetFullPower(Powers(powerType->PowerTypeEnum));
 
     // update level to hunter/summon pet
     if (Pet* pet = GetPet())
@@ -25523,7 +25543,7 @@ void Player::AtExitCombat()
 {
     Unit::AtExitCombat();
     UpdatePotionCooldown();
-    m_combatExitTime = getMSTime();
+    m_regenInterruptTimestamp = GameTime::Now();
 }
 
 float Player::GetBlockPercent(uint8 attackerLevel) const
diff --git a/src/server/game/Entities/Player/Player.h b/src/server/game/Entities/Player/Player.h
index 200b343b9c6..1130e870368 100644
--- a/src/server/game/Entities/Player/Player.h
+++ b/src/server/game/Entities/Player/Player.h
@@ -1747,6 +1747,7 @@ class TC_GAME_API Player : public Unit, public GridObject<Player>
         void SendRespecWipeConfirm(ObjectGuid const& guid, uint32 cost, SpecResetType respecType) const;
         void RegenerateAll();
         void Regenerate(Powers power);
+        void InterruptPowerRegen(Powers power);
         void RegenerateHealth();
         void setRegenTimerCount(uint32 time) {m_regenTimerCount = time;}
         void setWeaponChangeTimer(uint32 time) {m_weaponChangeTimer = time;}
@@ -2875,7 +2876,7 @@ class TC_GAME_API Player : public Unit, public GridObject<Player>
     protected:
         // Gamemaster whisper whitelist
         GuidList WhisperList;
-        uint32 m_combatExitTime;
+        TimePoint m_regenInterruptTimestamp;
         uint32 m_regenTimerCount;
         uint32 m_foodEmoteTimerCount;
         float m_powerFraction[MAX_POWERS_PER_CLASS];
diff --git a/src/server/game/Entities/Unit/StatSystem.cpp b/src/server/game/Entities/Unit/StatSystem.cpp
index 2fe2924702b..2e1f248ecc7 100644
--- a/src/server/game/Entities/Unit/StatSystem.cpp
+++ b/src/server/game/Entities/Unit/StatSystem.cpp
@@ -86,6 +86,17 @@ void Unit::UpdateDamagePhysical(WeaponAttackType attType)
     }
 }
 
+int32 Unit::GetCreatePowerValue(Powers power) const
+{
+    if (power == POWER_MANA)
+        return GetCreateMana();
+
+    if (PowerTypeEntry const* powerType = sDB2Manager.GetPowerTypeEntry(power))
+        return powerType->MaxBasePower;
+
+    return 0;
+}
+
 /*#######################################
 ########                         ########
 ########   PLAYERS STAT SYSTEM   ########
@@ -874,6 +885,15 @@ void Player::_RemoveAllStatBonuses()
 ########                         ########
 #######################################*/
 
+int32 Creature::GetCreatePowerValue(Powers power) const
+{
+    if (PowerTypeEntry const* powerType = sDB2Manager.GetPowerTypeEntry(power))
+        if (!powerType->GetFlags().HasFlag(PowerTypeFlags::IsUsedByNPCs))
+            return 0;
+
+    return Unit::GetCreatePowerValue(power);
+}
+
 bool Creature::UpdateStats(Stats /*stat*/)
 {
     return true;
@@ -910,10 +930,21 @@ uint32 Creature::GetPowerIndex(Powers power) const
 {
     if (power == GetPowerType())
         return 0;
-    if (power == POWER_ALTERNATE_POWER)
-        return 1;
-    if (power == POWER_COMBO_POINTS)
-        return 2;
+    switch (power)
+    {
+        case POWER_COMBO_POINTS:
+            return 2;
+        case POWER_ALTERNATE_POWER:
+            return 1;
+        case POWER_ALTERNATE_QUEST:
+            return 3;
+        case POWER_ALTERNATE_ENCOUNTER:
+            return 4;
+        case POWER_ALTERNATE_MOUNT:
+            return 5;
+        default:
+            break;
+    }
     return MAX_POWERS;
 }
 
diff --git a/src/server/game/Entities/Unit/Unit.cpp b/src/server/game/Entities/Unit/Unit.cpp
index 91247e8166a..98fd0ff18a2 100644
--- a/src/server/game/Entities/Unit/Unit.cpp
+++ b/src/server/game/Entities/Unit/Unit.cpp
@@ -5472,7 +5472,7 @@ void Unit::SetPowerType(Powers new_powertype, bool sendUpdate/* = true*/)
     }
 }
 
-void Unit::UpdateDisplayPower()
+Powers Unit::CalculateDisplayPowerType() const
 {
     Powers displayPower = POWER_MANA;
     switch (GetShapeshiftForm())
@@ -5496,22 +5496,18 @@ void Unit::UpdateDisplayPower()
                 AuraEffect const* powerTypeAura = powerTypeAuras.front();
                 displayPower = Powers(powerTypeAura->GetMiscValue());
             }
-            else if (GetTypeId() == TYPEID_PLAYER)
+            else
             {
                 ChrClassesEntry const* cEntry = sChrClassesStore.LookupEntry(GetClass());
                 if (cEntry && cEntry->DisplayPower < MAX_POWERS)
                     displayPower = Powers(cEntry->DisplayPower);
-            }
-            else if (GetTypeId() == TYPEID_UNIT)
-            {
+
                 if (Vehicle* vehicle = GetVehicleKit())
                 {
                     if (PowerDisplayEntry const* powerDisplay = sPowerDisplayStore.LookupEntry(vehicle->GetVehicleInfo()->PowerDisplayID[0]))
                         displayPower = Powers(powerDisplay->ActualType);
-                    else if (GetClass() == CLASS_ROGUE)
-                        displayPower = POWER_ENERGY;
                 }
-                else if (Pet* pet = ToPet())
+                else if (Pet const* pet = ToPet())
                 {
                     if (pet->getPetType() == HUNTER_PET) // Hunter pets have focus
                         displayPower = POWER_FOCUS;
@@ -5523,7 +5519,12 @@ void Unit::UpdateDisplayPower()
         }
     }
 
-    SetPowerType(displayPower);
+    return displayPower;
+}
+
+void Unit::UpdateDisplayPower()
+{
+    SetPowerType(CalculateDisplayPowerType());
 }
 
 void Unit::SetSheath(SheathState sheathed)
@@ -6496,6 +6497,11 @@ void Unit::SendEnergizeSpellLog(Unit* victim, uint32 spellID, int32 damage, int3
 
 void Unit::EnergizeBySpell(Unit* victim, SpellInfo const* spellInfo, int32 damage, Powers powerType)
 {
+    if (Player* player = victim->ToPlayer())
+        if (PowerTypeEntry const* powerTypeEntry = sDB2Manager.GetPowerTypeEntry(powerType))
+            if (powerTypeEntry->GetFlags().HasFlag(PowerTypeFlags::UseRegenInterrupt))
+                player->InterruptPowerRegen(powerType);
+
     int32 gain = victim->ModifyPower(powerType, damage, false);
     int32 overEnergize = damage - gain;
     victim->GetThreatManager().ForwardThreatForAssistingMe(this, float(damage) / 2, spellInfo, true);
@@ -9310,17 +9316,6 @@ void Unit::TriggerOnPowerChangeAuras(Powers power, int32 oldVal, int32 newVal)
     }
 }
 
-int32 Unit::GetCreatePowerValue(Powers power) const
-{
-    if (power == POWER_MANA)
-        return GetCreateMana();
-
-    if (PowerTypeEntry const* powerType = sDB2Manager.GetPowerTypeEntry(power))
-        return powerType->MaxBasePower;
-
-    return 0;
-}
-
 void Unit::AIUpdateTick(uint32 diff)
 {
     if (UnitAI* ai = GetAI())
diff --git a/src/server/game/Entities/Unit/Unit.h b/src/server/game/Entities/Unit/Unit.h
index 06f8076df6d..d12fbda04bd 100644
--- a/src/server/game/Entities/Unit/Unit.h
+++ b/src/server/game/Entities/Unit/Unit.h
@@ -915,6 +915,7 @@ class TC_GAME_API Unit : public WorldObject
         Powers GetPowerType() const { return Powers(*m_unitData->DisplayPower); }
         void SetPowerType(Powers power, bool sendUpdate = true);
         void SetOverrideDisplayPowerId(uint32 powerDisplayId) { SetUpdateFieldValue(m_values.ModifyValue(&Unit::m_unitData).ModifyValue(&UF::UnitData::OverrideDisplayPowerID), powerDisplayId); }
+        Powers CalculateDisplayPowerType() const;
         void UpdateDisplayPower();
         int32 GetPower(Powers power) const;
         int32 GetMinPower(Powers power) const { return power == POWER_LUNAR_POWER ? -100 : 0; }
@@ -1490,7 +1491,7 @@ class TC_GAME_API Unit : public WorldObject
         uint32 GetCreateHealth() const { return m_unitData->BaseHealth; }
         void SetCreateMana(uint32 val) { SetUpdateFieldValue(m_values.ModifyValue(&Unit::m_unitData).ModifyValue(&UF::UnitData::BaseMana), val); }
         uint32 GetCreateMana() const { return m_unitData->BaseMana; }
-        int32 GetCreatePowerValue(Powers power) const;
+        virtual int32 GetCreatePowerValue(Powers power) const;
         float GetPosStat(Stats stat) const { return m_unitData->StatPosBuff[stat]; }
         float GetNegStat(Stats stat) const { return m_unitData->StatNegBuff[stat]; }
         float GetCreateStat(Stats stat) const { return m_createStats[stat]; }
diff --git a/src/server/game/Server/Packets/CombatPackets.cpp b/src/server/game/Server/Packets/CombatPackets.cpp
index 97d56755cba..d662128556f 100644
--- a/src/server/game/Server/Packets/CombatPackets.cpp
+++ b/src/server/game/Server/Packets/CombatPackets.cpp
@@ -114,6 +114,13 @@ WorldPacket const* WorldPackets::Combat::PowerUpdate::Write()
     return &_worldPacket;
 }
 
+WorldPacket const* WorldPackets::Combat::InterruptPowerRegen::Write()
+{
+    _worldPacket << int32(PowerType);
+
+    return &_worldPacket;
+}
+
 void WorldPackets::Combat::SetSheathed::Read()
 {
     _worldPacket >> CurrentSheathState;
diff --git a/src/server/game/Server/Packets/CombatPackets.h b/src/server/game/Server/Packets/CombatPackets.h
index 6163fb81aca..4aaa57ceba9 100644
--- a/src/server/game/Server/Packets/CombatPackets.h
+++ b/src/server/game/Server/Packets/CombatPackets.h
@@ -22,6 +22,7 @@
 #include "ObjectGuid.h"
 
 class Unit;
+enum Powers : int8;
 
 namespace WorldPackets
 {
@@ -166,6 +167,16 @@ namespace WorldPackets
             std::vector<PowerUpdatePower> Powers;
         };
 
+        class InterruptPowerRegen final : public ServerPacket
+        {
+        public:
+            explicit InterruptPowerRegen(Powers powerType) : ServerPacket(SMSG_INTERRUPT_POWER_REGEN, 4), PowerType(powerType) { }
+
+            WorldPacket const* Write() override;
+
+            Powers PowerType;
+        };
+
         class SetSheathed final : public ClientPacket
         {
         public:
diff --git a/src/server/game/Server/Protocol/Opcodes.cpp b/src/server/game/Server/Protocol/Opcodes.cpp
index f2a0db0a797..93c375257fa 100644
--- a/src/server/game/Server/Protocol/Opcodes.cpp
+++ b/src/server/game/Server/Protocol/Opcodes.cpp
@@ -1528,7 +1528,7 @@ void OpcodeTable::Initialize()
     DEFINE_SERVER_OPCODE_HANDLER(SMSG_INSTANCE_RESET,                          STATUS_NEVER,        CONNECTION_TYPE_REALM);
     DEFINE_SERVER_OPCODE_HANDLER(SMSG_INSTANCE_RESET_FAILED,                   STATUS_NEVER,        CONNECTION_TYPE_REALM);
     DEFINE_SERVER_OPCODE_HANDLER(SMSG_INSTANCE_SAVE_CREATED,                   STATUS_NEVER,        CONNECTION_TYPE_REALM);
-    DEFINE_SERVER_OPCODE_HANDLER(SMSG_INTERRUPT_POWER_REGEN,                   STATUS_UNHANDLED,    CONNECTION_TYPE_INSTANCE);
+    DEFINE_SERVER_OPCODE_HANDLER(SMSG_INTERRUPT_POWER_REGEN,                   STATUS_NEVER,        CONNECTION_TYPE_INSTANCE);
     DEFINE_SERVER_OPCODE_HANDLER(SMSG_INVALIDATE_PAGE_TEXT,                    STATUS_UNHANDLED,    CONNECTION_TYPE_REALM);
     DEFINE_SERVER_OPCODE_HANDLER(SMSG_INVALIDATE_PLAYER,                       STATUS_NEVER,        CONNECTION_TYPE_REALM);
     DEFINE_SERVER_OPCODE_HANDLER(SMSG_INVALID_PROMOTION_CODE,                  STATUS_UNHANDLED,    CONNECTION_TYPE_REALM);
diff --git a/src/server/game/World/World.cpp b/src/server/game/World/World.cpp
index d849a261698..3bf7c0a6c58 100644
--- a/src/server/game/World/World.cpp
+++ b/src/server/game/World/World.cpp
@@ -631,6 +631,7 @@ void World::LoadConfigSettings(bool reload)
     setRegenRate(RATE_POWER_ARCANE_CHARGES, "Rate.ArcaneCharges.Loss");
     setRegenRate(RATE_POWER_FURY, "Rate.Fury.Loss");
     setRegenRate(RATE_POWER_PAIN, "Rate.Pain.Loss");
+    setRegenRate(RATE_POWER_ESSENCE, "Rate.Essence.Loss");
 
     rate_values[RATE_SKILL_DISCOVERY]      = sConfigMgr->GetFloatDefault("Rate.Skill.Discovery", 1.0f);
     rate_values[RATE_DROP_ITEM_POOR]       = sConfigMgr->GetFloatDefault("Rate.Drop.Item.Poor", 1.0f);
diff --git a/src/server/game/World/World.h b/src/server/game/World/World.h
index 3be26d65a9c..cb2973cc6a8 100644
--- a/src/server/game/World/World.h
+++ b/src/server/game/World/World.h
@@ -463,6 +463,7 @@ enum Rates
     RATE_POWER_ARCANE_CHARGES,
     RATE_POWER_FURY,
     RATE_POWER_PAIN,
+    RATE_POWER_ESSENCE,
     RATE_SKILL_DISCOVERY,
     RATE_DROP_ITEM_POOR,
     RATE_DROP_ITEM_NORMAL,
diff --git a/src/server/worldserver/worldserver.conf.dist b/src/server/worldserver/worldserver.conf.dist
index fe35b9c0320..4180cbd2b5c 100644
--- a/src/server/worldserver/worldserver.conf.dist
+++ b/src/server/worldserver/worldserver.conf.dist
@@ -2414,6 +2414,7 @@ Rate.Insanity.Loss     = 1
 Rate.ArcaneCharges.Loss= 1
 Rate.Fury.Loss         = 1
 Rate.Pain.Loss         = 1
+Rate.Essence.Loss      = 1
 
 #
 #    Rate.Skill.Discovery