Deckard Cain

Cain in-game.

Deckard Cain concept art.

Deckard Cain is an essential NPC in the Diablo universe. As a wise sage and the last of the Horadrim, Cain has played an important part in both Diablo 1 and Diablo 2 games. This old, classic Diablo character will definitely ask you to stay a while and listen.

Deckard Cain is seen in the gameplay video from the WWI 2008. In the gameplay video the player rescues Cain once again, apparently in the New Tristram Cathedral.

There is mention of Deckard Cain on the main page of the official page:

"When Deckard Cain returns to the ruins of Tristram Cathedral seeking clues to defeat new stirrings of evil, a fiery harbinger of doom falls from the heavens, striking the very ground where Diablo once entered the world."

There is also a lore item on the official D3 site; Deckard Cain's journal. It summarizes the story as so far revealed in Diablo and Diablo II.

Michael Gough, the voice actor who has played Deckard Cain in all three games, was recently interviewed.