Tome of Berserker IV

Effect
Use into Skills Master to learn skill Berserker IV: increases the Critical Strike rate of this hero's units by 180 points. Can be used for hero with level 70 or higher and speciality Attack.

Obtain
It can be found in:
 * Wheel of Fortune.
 * Purgatory Abyss Layer.
 * Purgatory Abyss Layer.