I think I had a level 5 or 6 focus. I was holding a Tome of Lost Knowledge which has 15% SDI and using WoD on Navrey, result 345 damage. I dropped the ToLK and picked up a regular magery spellbook with Spider Slayer and used WoD on Navrey, result 300 damage. I dropped the regular magery spellbook, left my hands empty and used WoD on Navrey, result 300 damage. Should I be getting 2x-3x damage when I use a slayer? What am I missing here? Thanks, in advance.