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Located at 4512, 10134 in the Temple of Thontic in Ardent Domain. The book is found on a bench, You have to mount up and run to the benches it teleports to. Once it is done it will port to the altar where you have to kill the named mob before you can read it. Reading it takes about 15 seconds. If you are fast enough you can read it twice before the mob respawns. Reading the book awards the achievement and "A Blob of Ectoplasm" item which is used for a puzzle in Seratos. You need three of these items.