The Book of Skill.

The Book of Skill is an unreadable Tome item in Act II of Diablo II. It can be obtained after defeating Radament for the first time, completing the Radament's Lair quest. Upon 'reading' the Book of Skill the player is rewarded with one Skill Point. Note that the Book of Skill drops only once per Difficulty: you cannot 'farm' Books of Skill by repeatedly killing Radament.

Story TomesMoldy TomeHorazon's Journal
ItemsBook of Skill Lam Esen's TomeTome of Town PortalTome of Identify
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