public class Item  {

   public string lootID;
   public string lootSpriteID;
   public string lootName;
   public string lootDescription;
   public int amount;
}

public enum ITEMQUALITY
{
   common,
   unique,
   rare,
   epic,
   legendary   
}

public class Artifact: Item  {

public ITEMQUALITY itemQuality;
public static List<Artifact> ArtifactsInStack = new List<Artifact>();

public  Artifact(string lootID,string lootSpriteID,string lootName,string lootDescription, int amount, ITEMQUALITY itemQuality = ITEMQUALITY.common ){

this.lootID = lootID;
this.lootSpriteID = lootSpriteID;
this.lootName = lootName;
this.lootDescription = lootDescription;
this.amount = amount;
this.itemQuality = itemQuality;

ArtifactsInStack.Add(this);

}

}

void Start(){

// создаем новые артефакты
new Artifact("sword","sprite_sword,"меч","крутой меч",1);
new Artifact("bow","sprite_bow,"лук","крутой лук",1,ITEMQUALITY.epic);

// зачем то выбираем лук   
Artifact selectedArtifact = Artifact.ArtifactsInStack.Find(item=>item.lootID == "bow");

}

void shBlock ()
     {
          
      if (MonsterClass.tempInstance == null)
       return;
          
      MonsterClass.tempInstance.event_attackDamage += shBlock_handler;
          
     }

public void shBlock_handler (ref int val)
     {
       if (Random.Range (0f, 100f) > Traits ["shBlock"].baseVal)
       return;
          
      val = Mathf.CeilToInt (val * 0.5f);
          
          
     }