The Tale of the Three is a tome found on the 8th level of the catacombs in the original Diablo. It is presumably written by Archbishop Lazarus.

It reads as follows:

"Glory and approbation to Diablo, Lord of Terror and Leader of the Three. My Lord spoke to me of his two brothers, Mephisto and Baal, who were banished to this world long ago. My Lord wishes to bide his time and harness his awesome power so that he may free his captive brothers from their tombs beneath the sands of the East. Once my Lord releases his brothers, The Sin War will once again know the fury of the Three."
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