Core/Spells: ported PROC_FLAG_ENTER_COMBAT implementation from master branch and handle the Worgen transformation via its proc aura

src/server/scripts/Spells/spell_generic.cpp

@@ -3009,6 +3009,30 @@ class spell_gen_darkflight : public SpellScriptLoader
             return new spell_gen_darkflight_SpellScript();
         }
 };
+
+enum AlteredForm
+{
+    SPELL_ALTERED_FORM_PROC_AURA = 97681 // Serverside spell
+};
+
+class spell_gen_enable_worgen_altered_form : public AuraScript
+{
+    bool Validate(SpellInfo const* /*spellInfo*/) override
+    {
+        return ValidateSpellInfo({ SPELL_ALTERED_FORM_PROC_AURA });
+    }
+
+    void HandleApply(AuraEffect const* /*aurEff*/, AuraEffectHandleModes /*mode*/)
+    {
+        GetTarget()->CastSpell(nullptr, SPELL_ALTERED_FORM_PROC_AURA, true);
+    }
+
+    void Register() override
+    {
+        AfterEffectApply.Register(&spell_gen_enable_worgen_altered_form::HandleApply, EFFECT_0, SPELL_AURA_ENABLE_ALTERED_FORM, AURA_EFFECT_HANDLE_REAL_OR_REAPPLY_MASK);
+    }
+};
+
 enum SeaforiumSpells
 {
     SPELL_PLANT_CHARGES_CREDIT_ACHIEVEMENT  = 60937
@@ -5450,6 +5474,7 @@ void AddSC_generic_spell_scripts()
     new spell_gen_running_wild();
     new spell_gen_two_forms();
     new spell_gen_darkflight();
+    RegisterSpellScript(spell_gen_enable_worgen_altered_form);
     /*                          */
     new spell_gen_seaforium_blast();
     new spell_gen_spectator_cheer_trigger();