This is a passive skill that increases the number of character buffs. For each skill level, the character is added 1 buff slot. Maximum - 24 buff-slots . You do not need to spend sp to learn it, but you need to spend a special book for each skill level.
This book is sold by NPC Black Marketeer of Mammon. You can find him in every city. He hides, but not too much.
This book falls from raid bosses. Practically from all raid bosses 70+ level. Including you can knock out a book from Anakazel in the rift 70+.
Anakazel - Invader's Leader (68)
Anakim's Nemesis Zakaron (70)
Antharas Priest Cloe (74)
Beast Lord Behemoth (70)
Bloody Priest Rudelto (69)
Death Lord Hallate (73)
Demon's Agent Falston (66)
Doom Blade Tanatos (72)
Einhalder Von Hellmann (71)
Fafurion's Herald Lokness (70)
Flame of Splendor Barakiel (70)
Icicle Emperor Bumbalump (74)
Immortal Savior Mardil (71)
Kernon's Faithful Servant Kelone (67)
Krokian Padisha Sobekk (74)
Last Titan Utenus (66)
Meanas Anor (70)
Pague Golem (73)
Palibari Queen Themis (70)
Roaring Skylancer (70)
Shilen's Messenger Cabrio (70)
Spirit of Andras, The Betrayer (69)
Vanor Chief Kandra (72)
Water Dragon Seer Sheshark (72)
This book falls from the epic raid bosses: Baium, Frintezza, Antharas, Valakas. Falls them not one piece, but immediately to the top ten. But the boss still needs to be killed.
This book is sold to participants in the Olympics for the noble gate passes. And there are 450 thousand of these most gates of passes. Even more interesting is that the book can not be transferred to others or dropped. That is, you will have to buy it on your own olympiad points.
Note: In Gracia Final chronicle you can also get the Ancient Book - Divine Inspiration (Original Language Version) - LVL 61 and Ancient Book - Divine Inspiration (Manuscript) - LVL 76 by doing the How to Oppose Evil quest in Gracia (started at NPC Dilos) and buy the Book from Kirklan NPC.