Izzal was amazed at the weapon that I obtained at The Tabernacle of Pain.
He explained that it is the reformed metal tablets that once held the tenants of Marr, it The Truth of Marr spent a detrimental amount of time within the demi-plane The Sphere of Malevolence, and as a result of that time it has become corrupted.
He believes that there must be a way to cleanse the sword and restore it to its prior glory.