Move creature min/max level check to objectmgr

sql/migrations/20250418172108_world.sql

@@ -0,0 +1,20 @@
+DROP PROCEDURE IF EXISTS add_migration;
+DELIMITER ??
+CREATE PROCEDURE `add_migration`()
+BEGIN
+DECLARE v INT DEFAULT 1;
+SET v = (SELECT COUNT(*) FROM `migrations` WHERE `id`='20250418172108');
+IF v = 0 THEN
+INSERT INTO `migrations` VALUES ('20250418172108');
+-- Add your query below.
+
+-- Correct levelrange for Morbent Fel Pre 1.6
+
+UPDATE `creature_template` SET `level_max`=35 WHERE  `entry`=1200 AND `patch`=0;
+
+-- End of migration.
+END IF;
+END??
+DELIMITER ;
+CALL add_migration();
+DROP PROCEDURE IF EXISTS add_migration;

src/game/ObjectMgr.cpp

@@ -1620,6 +1620,14 @@ void ObjectMgr::CheckCreatureTemplate(CreatureInfo* cInfo)
             sLog.Out(LOG_DBERROR, LOG_LVL_MINIMAL, "Creature (Entry: %u) with despawn instantly flag has skinning loot assigned. It will never be lootable.", cInfo->entry);
     }
 
+    if (cInfo->level_min > cInfo->level_max)
+    {
+        uint32 tmp = cInfo->level_min;
+        cInfo->level_min = cInfo->level_max;
+        cInfo->level_max = tmp;
+        sLog.Out(LOG_DBERROR, LOG_LVL_MINIMAL, "Creature (Entry: %u) has level_min (%u) greater than level_max (%u), values have been swapped.", cInfo->entry, cInfo->level_max, cInfo->level_min);
+    }
+
     ConvertCreatureAurasField<CreatureInfo>(cInfo, "creature_template", "Entry", cInfo->entry);
 }
 

src/game/Objects/Creature.cpp

@@ -1703,8 +1703,8 @@ void Creature::SelectLevel(float percentHealth, float percentMana)
     CreatureInfo const* cinfo = GetCreatureInfo();
 
     // level
-    uint32 const minLevel = std::min(cinfo->level_max, cinfo->level_min);
-    uint32 const maxLevel = std::max(cinfo->level_max, cinfo->level_min);
+    uint32 const minLevel = cinfo->level_min;
+    uint32 const maxLevel = cinfo->level_max;
     uint32 const level = minLevel == maxLevel ? minLevel : urand(minLevel, maxLevel);
 
     SetLevel(level);