Core/DB: Fix spellscript validation startup errors

Closes #44

src/server/scripts/Spells/spell_dk.cpp

@@ -390,6 +390,13 @@ class spell_dk_death_and_decay : public SpellScriptLoader
         {
             PrepareAuraScript(spell_dk_death_and_decay_AuraScript);
 
+            bool Validate(SpellInfo const* /*spellInfo*/) override
+            {
+                if (!sSpellMgr->GetSpellInfo(SPELL_DK_DEATH_AND_DECAY_DAMAGE))
+                    return false;
+                return true;
+            }
+
             void HandleDummyTick(AuraEffect const* aurEff)
             {
                 if (Unit* caster = GetCaster())
@@ -398,7 +405,7 @@ class spell_dk_death_and_decay : public SpellScriptLoader
 
             void Register() override
             {
-                OnEffectPeriodic += AuraEffectPeriodicFn(spell_dk_death_and_decay_AuraScript::HandleDummyTick, EFFECT_0, SPELL_AURA_PERIODIC_DUMMY);
+                OnEffectPeriodic += AuraEffectPeriodicFn(spell_dk_death_and_decay_AuraScript::HandleDummyTick, EFFECT_1, SPELL_AURA_PERIODIC_DUMMY);
             }
         };