Unspeakable tome
Superior
Cost: 15 gp
Weight: 3 lb.
An unspeakable tome is bound in straps of iron so that it cannot be opened, but it imparts the knowledge it contains through sinister whispers in the night.
Properties:
Empowered Crit (When you score a critical hit with an empowered crit implement, the attack deals 1d10 extra damage. The extra damage increases to 2d10 at 11th level and 3d10 at 21st level.).
Undeniable (You gain a +1 bonus to attack rolls against Will when attacking with an undeniable implement.).
Group:
Tome (Most tomes contain one or more wizard spells, often supplemented by information on improving the spells' effectiveness. You can't make melee attacks with a tome.
If you are a member of a class that can wield a tome as an implement, you can add the tome's enhancement bonus to the attack rolls and the damage rolls of implement powers from that class that you use through the tome, and you can use its properties and powers. Members of other classes gain no benefit from wielding a tome.).
Published in Player's Handbook 3, page(s) 195, Mordenkainen's Magnificent Emporium, page(s) 40.