diff --git a/sql/updates/world/4.3.4/2021_02_22_00_world.sql b/sql/updates/world/4.3.4/2021_02_22_00_world.sql
new file mode 100644
index 00000000000..5a245c119b1
--- /dev/null
+++ b/sql/updates/world/4.3.4/2021_02_22_00_world.sql
@@ -0,0 +1,95 @@
+UPDATE `creature_template` SET `ScriptName`= '', `unit_flags`= 0x40 | 0x8000 | 0x2000000, `flags_extra`= 128 WHERE `entry`= 40790;
+UPDATE `creature` SET `ScriptName`= 'npc_hoo_aggro_stalker_1' WHERE `guid`= 307307;
+UPDATE `creature` SET `ScriptName`= 'npc_hoo_aggro_stalker_2' WHERE `guid`= 307365;
+UPDATE `creature` SET `ScriptName`= 'npc_hoo_aggro_stalker_3' WHERE `guid`= 308039;
+
+UPDATE `creature_template` SET `unit_flags`= 0x40 WHERE `entry` IN (39440, 49286, 40310, 49294, 40787, 49301, 42556, 49306);
+DELETE FROM `creature_template_addon` WHERE `entry` IN (39440, 49286, 40310, 49294, 40787, 49301, 42556, 49306);
+
+DELETE FROM `creature_template_movement` WHERE `CreatureId`= 40790;
+INSERT INTO `creature_template_movement` (`CreatureId`, `Ground`, `Swim`, `Flight`, `Rooted`) VALUES
+(40790, 0, 0, 1, 1);
+
+DELETE FROM `creature` WHERE `guid` IN (307310, 307308, 307320, 307360, 307333, 307453, 307418, 307452, 307454, 307680, 307678, 307679);
+DELETE FROM `creature_addon` WHERE `guid` IN (307310, 307308, 307320, 307360, 307333, 307453, 307418, 307452, 307454, 307680, 307678, 307679);
+DELETE FROM `creature_formations` WHERE `LeaderGUID` IN (307307, 307365, 308039);
+
+DELETE FROM `creature_summon_groups` WHERE `summonerId`= 40790 AND `summonerType`= 0;
+INSERT INTO `creature_summon_groups` (`summonerId`, `summonerType`, `groupId`, `entry`, `position_x`, `position_y`, `position_z`, `orientation`, `summonType`,`summonTime`) VALUES
+-- 0
+(40790, 0, 0, 42556, -496.333, 97.9983, 83.1642, 3.80482, 6, 60000),
+(40790, 0, 0, 42556, -492.167, 80.0035, 82.4928, 2.11185, 6, 60000),
+(40790, 0, 0, 39440, -519.724, 77.1198, 83.2052, 0.628318, 6, 60000),
+-- 1
+(40790, 0, 1, 42556, -514.592, 26.8125, 82.3194, 1.25664, 6, 60000),
+(40790, 0, 1, 42556, -514.471, 47.0625, 83.2324, 4.92183, 6, 60000),
+(40790, 0, 1, 42556, -489.51,  48.5156, 86.2949, 3.56047, 6, 60000),
+(40790, 0, 1, 40787, -520.404, 35.3941, 84.3484, 1.25664, 6, 60000),
+(40790, 0, 1, 40310, -492.373, 38.559,  83.9584, 1.95477, 6, 60000),
+-- 2
+(40790, 0, 2, 42556, -496.715, -12.2135, 83.0425, 2.23402, 6, 60000),
+(40790, 0, 2, 42556, -522.835, -8.40451, 83.8212, 6.16101, 6, 60000),
+(40790, 0, 2, 40311, -490.234, -18.5382, 83.1895, 1.8326, 6, 60000),
+(40790, 0, 2, 39440, -524.488, -17.651, 83.6682, 0, 6, 60000);
+
+DELETE FROM `spell_script_names` WHERE `ScriptName`= 'spell_hoo_submerge';
+INSERT INTO `spell_script_names` (`spell_id`, `ScriptName`) VALUES
+(76084, 'spell_hoo_submerge');
+
+-- Creature Venomous Skitterer 39440 SAI
+SET @ENTRY := 39440;
+UPDATE `creature_template` SET `AIName`="SmartAI" WHERE `entry`= @ENTRY;
+DELETE FROM `smart_scripts` WHERE `entryorguid`=@ENTRY AND `source_type`=0;
+INSERT INTO `smart_scripts` (`entryorguid`, `source_type`, `id`, `link`, `event_type`, `event_phase_mask`, `event_chance`, `event_flags`, `event_param1`, `event_param2`, `event_param3`, `event_param4`, `action_type`, `action_param1`, `action_param2`, `action_param3`, `action_param4`, `action_param5`, `action_param6`, `target_type`, `target_param1`, `target_param2`, `target_param3`, `target_x`, `target_y`, `target_z`, `target_o`, `comment`) VALUES
+(@ENTRY, 0, 0, 0, 0, 0, 100, 0, 2400, 2400, 15000, 16000, 11, 75158, 0, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0, "Update (In Combat) 2400 min and 2400 max ms (repeat 15000 min 16000 max ms) - Self: Cast spell Surge (75158) on Random hostile // "),
+(@ENTRY, 0, 1, 0, 0, 0, 100, 0, 4000, 5000, 17000, 19000, 11, 74121, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, "Update (In Combat) 4000 min and 5000 max ms (repeat 17000 min 19000 max ms) - Self: Cast spell Debilitating Venom (74121) on Victim // "),
+(@ENTRY, 0, 2, 0, 0, 0, 100, 0, 9000, 10000, 30000, 31000, 11, 73963, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, "Update (In Combat) 9000 min and 10000 max ms (repeat 30000 min 31000 max ms) - Self: Cast spell Blinding Toxin (73963) on Victim // ");
+
+-- Creature Jeweled Scarab 42556 SAI
+SET @ENTRY := 42556;
+UPDATE `creature_template` SET `AIName`="SmartAI" WHERE `entry`= @ENTRY;
+DELETE FROM `smart_scripts` WHERE `entryorguid`=@ENTRY AND `source_type`=0;
+INSERT INTO `smart_scripts` (`entryorguid`, `source_type`, `id`, `link`, `event_type`, `event_phase_mask`, `event_chance`, `event_flags`, `event_param1`, `event_param2`, `event_param3`, `event_param4`, `action_type`, `action_param1`, `action_param2`, `action_param3`, `action_param4`, `action_param5`, `action_param6`, `target_type`, `target_param1`, `target_param2`, `target_param3`, `target_x`, `target_y`, `target_z`, `target_o`, `comment`) VALUES
+(@ENTRY, 0, 0, 0, 0, 0, 100, 0, 2400, 2400, 13000, 16000, 11, 83233, 0, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0, "Update (In Combat) 2400 min and 2400 max ms (repeat 13000 min 16000 max ms) - Self: Cast spell Surge (83233) on Random hostile // ");
+
+-- Creature Blistering Scarab 40310 SAI
+SET @ENTRY := 40310;
+UPDATE `creature_template` SET `AIName`="SmartAI" WHERE `entry`= @ENTRY;
+DELETE FROM `smart_scripts` WHERE `entryorguid`=@ENTRY AND `source_type`=0;
+INSERT INTO `smart_scripts` (`entryorguid`, `source_type`, `id`, `link`, `event_type`, `event_phase_mask`, `event_chance`, `event_flags`, `event_param1`, `event_param2`, `event_param3`, `event_param4`, `action_type`, `action_param1`, `action_param2`, `action_param3`, `action_param4`, `action_param5`, `action_param6`, `target_type`, `target_param1`, `target_param2`, `target_param3`, `target_x`, `target_y`, `target_z`, `target_o`, `comment`) VALUES
+(@ENTRY, 0, 0, 0, 0, 0, 100, 0, 4000, 4000, 3500, 4000, 11, 74122, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, "Update (In Combat) 4000 min and 4000 max ms (repeat 3500 min 4000 max ms) - Self: Cast spell Corrosive Spray (74122) on Self // "),
+(@ENTRY, 0, 1, 0, 0, 0, 100, 0, 7000, 8000, 10000, 11000, 11, 74542, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, "Update (In Combat) 7000 min and 8000 max ms (repeat 10000 min 11000 max ms) - Self: Cast spell Serrated Slash (74542) on Victim // ");
+
+-- Creature Dustbone Horror 40787 SAI
+SET @ENTRY := 40787;
+UPDATE `creature_template` SET `AIName`="SmartAI" WHERE `entry`= @ENTRY;
+DELETE FROM `smart_scripts` WHERE `entryorguid`=@ENTRY AND `source_type`=0;
+INSERT INTO `smart_scripts` (`entryorguid`, `source_type`, `id`, `link`, `event_type`, `event_phase_mask`, `event_chance`, `event_flags`, `event_param1`, `event_param2`, `event_param3`, `event_param4`, `action_type`, `action_param1`, `action_param2`, `action_param3`, `action_param4`, `action_param5`, `action_param6`, `target_type`, `target_param1`, `target_param2`, `target_param3`, `target_x`, `target_y`, `target_z`, `target_o`, `comment`) VALUES
+(@ENTRY, 0, 0, 0, 0, 0, 100, 0, 10000, 12000, 10000, 14000, 11, 75453, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, "Update (In Combat) 10000 min and 12000 max ms (repeat 10000 min 14000 max ms) - Self: Cast spell Smash (75453) on Victim // ");
+
+-- Creature Dustbone Tormentor 40311 SAI
+SET @ENTRY := 40311;
+UPDATE `creature_template` SET `AIName`="SmartAI" WHERE `entry`= @ENTRY;
+DELETE FROM `smart_scripts` WHERE `entryorguid`=@ENTRY AND `source_type`=0;
+INSERT INTO `smart_scripts` (`entryorguid`, `source_type`, `id`, `link`, `event_type`, `event_phase_mask`, `event_chance`, `event_flags`, `event_param1`, `event_param2`, `event_param3`, `event_param4`, `action_type`, `action_param1`, `action_param2`, `action_param3`, `action_param4`, `action_param5`, `action_param6`, `target_type`, `target_param1`, `target_param2`, `target_param3`, `target_x`, `target_y`, `target_z`, `target_o`, `comment`) VALUES
+(@ENTRY, 0, 0, 0, 0, 0, 100, 0, 6000, 6000, 43000, 45000, 11, 77357, 0, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0, "Update (In Combat) 6000 min and 6000 max ms (repeat 43000 min 45000 max ms) - Self: Cast spell Curse of Exhaustion (77357) on Random hostile // "),
+(@ENTRY, 0, 1, 0, 0, 0, 100, 0, 7000, 7000, 2400, 2400, 11, 77570, 64, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, "Update (In Combat) 7000 min and 7000 max ms (repeat 2400 min 2400 max ms) - Self: Cast spell Shadow Bolt (77570) on Victim // ");
+
+-- Creature Dustbone Horror 40808 SAI
+SET @ENTRY := 40808;
+UPDATE `creature_template` SET `AIName`="SmartAI" WHERE `entry`= @ENTRY;
+DELETE FROM `smart_scripts` WHERE `entryorguid`=@ENTRY AND `source_type`=0;
+INSERT INTO `smart_scripts` (`entryorguid`, `source_type`, `id`, `link`, `event_type`, `event_phase_mask`, `event_chance`, `event_flags`, `event_param1`, `event_param2`, `event_param3`, `event_param4`, `action_type`, `action_param1`, `action_param2`, `action_param3`, `action_param4`, `action_param5`, `action_param6`, `target_type`, `target_param1`, `target_param2`, `target_param3`, `target_x`, `target_y`, `target_z`, `target_o`, `comment`) VALUES
+(@ENTRY, 0, 0, 0, 37, 0, 100, 0, 0, 0, 0, 0, 42, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, "On AI initialize - Set Invulnerability Health level // "),
+(@ENTRY, 0, 1, 2, 2, 0, 100, 0, 0, 20, 60000, 60000, 46, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, "When health between 0% and 20% (check every 60000 - 60000 ms) - Stop Attacking // "),
+(@ENTRY, 0, 2, 3, 61, 0, 100, 0, 0, 0, 0, 0, 8, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, " Linked - Self: Set react state to REACT_PASSIVE // "),
+(@ENTRY, 0, 3, 4, 61, 0, 100, 0, 0, 0, 0, 0, 11, 76084, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, " Linked - Self: Cast spell Submerge (76084) on Self // "),
+(@ENTRY, 0, 4, 0, 61, 0, 100, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, " Linked - Self: Talk 0 // "),
+(@ENTRY, 0, 5, 0, 8, 0, 100, 0, 76084, 0, 0, 0, 41, 3000, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, "On spell Submerge (76084) hit  - Self: Despawn in 3000 ms // "),
+(@ENTRY, 0, 6, 0, 0, 0, 100, 0, 4000, 5000, 9000, 11000, 11, 75453, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, "Update (In Combat) 4000 min and 5000 max ms (repeat 9000 min 11000 max ms) - Self: Cast spell Smash (75453) on Victim // ");
+
+DELETE FROM `creature_text` WHERE `CreatureID`= 40808;
+INSERT INTO `creature_text` (`CreatureID`, `GroupID`, `ID`, `Text`, `Type`, `Language`, `Probability`, `Emote`, `Duration`, `Sound`, `BroadcastTextId`, `comment`) VALUES
+(40808, 0, 0, '%s buries itself in the sand!', 16, 0, 100, 0, 0, 0, 42474, '');
+
+UPDATE `creature_template` SET `mechanic_immune_mask`= `mechanic_immune_mask` | 0x800 WHERE `entry` IN (40808, 49302);
diff --git a/src/server/scripts/Kalimdor/HallsOfOrigination/halls_of_origination.cpp b/src/server/scripts/Kalimdor/HallsOfOrigination/halls_of_origination.cpp
index d78f5985404..a60232be480 100644
--- a/src/server/scripts/Kalimdor/HallsOfOrigination/halls_of_origination.cpp
+++ b/src/server/scripts/Kalimdor/HallsOfOrigination/halls_of_origination.cpp
@@ -117,6 +117,70 @@ private:
     bool _dispersed;
 };
 
+enum AggroStalker
+{
+    // Spells
+    SPELL_SUBMERGE  = 76084,
+    SPELL_EMERGE    = 75764
+};
+
+struct npc_hoo_aggro_stalker_base : public ScriptedAI
+{
+    npc_hoo_aggro_stalker_base(Creature* creature, uint8 summonGroupId) : ScriptedAI(creature), _summonGroupId(summonGroupId) { }
+
+    void InitializeAI() override
+    {
+        // Trigger creatures are passive by default but we need an aggressive one here.
+        me->SetReactState(REACT_AGGRESSIVE);
+    }
+
+    void JustAppeared() override
+    {
+        me->SummonCreatureGroup(_summonGroupId);
+    }
+
+    void AttackStart(Unit* /*who*/) override {  }
+
+    void JustEngagedWith(Unit* who) override
+    {
+        for (ObjectGuid const& guid : _summonGUIDs)
+        {
+            if (Creature* summon = ObjectAccessor::GetCreature(*me, guid))
+            {
+                summon->EngageWithTarget(who);
+                if (summon->HasAura(SPELL_SUBMERGE))
+                {
+                    summon->RemoveAurasDueToSpell(SPELL_SUBMERGE);
+                    summon->CastSpell(summon, SPELL_EMERGE);
+                }
+            }
+        }
+    }
+
+    void JustSummoned(Creature* summon) override
+    {
+        _summonGUIDs.insert(summon->GetGUID());
+        summon->CastSpell(summon, SPELL_SUBMERGE, true); // The spell has a cast time but we need them submerged immediately
+    }
+
+    void SummonedCreatureDies(Creature* summon, Unit* /*killer*/) override
+    {
+        _summonGUIDs.erase(summon->GetGUID());
+
+        // Group has been defeated, despawn aggro stalker.
+        if (_summonGUIDs.empty())
+            me->DespawnOrUnsummon();
+    }
+
+private:
+    uint8 _summonGroupId;
+    GuidSet _summonGUIDs;
+};
+
+struct npc_hoo_aggro_stalker_1 : public npc_hoo_aggro_stalker_base { npc_hoo_aggro_stalker_1(Creature* creature) : npc_hoo_aggro_stalker_base(creature, 0) { } };
+struct npc_hoo_aggro_stalker_2 : public npc_hoo_aggro_stalker_base { npc_hoo_aggro_stalker_2(Creature* creature) : npc_hoo_aggro_stalker_base(creature, 1) { } };
+struct npc_hoo_aggro_stalker_3 : public npc_hoo_aggro_stalker_base { npc_hoo_aggro_stalker_3(Creature* creature) : npc_hoo_aggro_stalker_base(creature, 2) { } };
+
 // The Maker's Lift
 enum ElevatorMisc
 {
@@ -230,10 +294,39 @@ class spell_hoo_disperse : public AuraScript
     }
 };
 
+class spell_hoo_submerge : public AuraScript
+{
+    void HandleFlagsAfterApply(AuraEffect const* /*aurEff*/, AuraEffectHandleModes /*mode*/)
+    {
+        Unit* target = GetTarget();
+        target->SetFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_NOT_SELECTABLE);
+        if (target->IsCreature())
+            target->ToCreature()->SetReactState(REACT_PASSIVE);
+    }
+
+    void HandleFlagsAfterRemove(AuraEffect const* /*aurEff*/, AuraEffectHandleModes /*mode*/)
+    {
+        Unit* target = GetTarget();
+        GetTarget()->RemoveFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_NOT_SELECTABLE);
+        if (target->IsCreature())
+            target->ToCreature()->SetReactState(REACT_AGGRESSIVE);
+    }
+
+    void Register() override
+    {
+        AfterEffectApply.Register(&spell_hoo_submerge::HandleFlagsAfterApply, EFFECT_0, SPELL_AURA_MOD_STUN, AURA_EFFECT_HANDLE_REAL);
+        AfterEffectRemove.Register(&spell_hoo_submerge::HandleFlagsAfterRemove, EFFECT_0, SPELL_AURA_MOD_STUN, AURA_EFFECT_HANDLE_REAL);
+    }
+};
+
 void AddSC_halls_of_origination()
 {
     RegisterHallsOfOriginationCreatureAI(npc_sun_touched_servant);
+    RegisterHallsOfOriginationCreatureAI(npc_hoo_aggro_stalker_1);
+    RegisterHallsOfOriginationCreatureAI(npc_hoo_aggro_stalker_2);
+    RegisterHallsOfOriginationCreatureAI(npc_hoo_aggro_stalker_3);
     RegisterGameObjectAI(go_hoo_the_makers_lift_controller);
     RegisterSpellScript(spell_hoo_flame_ring_visual);
     RegisterSpellScript(spell_hoo_disperse);
+    RegisterSpellScript(spell_hoo_submerge);
 }