DiabloFans has interviewed Michael Gough, the voice actor responsible for Deckard Cain in all three Diablo games. He can't reveal much of anything from the upcoming Diablo III, so the discussion focuses mostly on how he does what he does.
DiabloFans: How much creativity were you allowed as a whole? Say, between the accent, lines, misc sounds, etc...
Gough: Once there is a script, I don't think I have a lot of creative license to change the script too much. Certain sentences or language or sounds may be different once spoken. I started out that way, with 'just a little bit of Sean Connery', and I think that was one of their suggestions when we tried it. Once I said it, it pretty much stayed that way.
With Diablo III coming out, there's more emotional value to it, I guess you could say. It doesn't necessarily change the voice and the accent, but it makes him sound a little different just because there is more going on underneath. Cain is going through things that maybe he hasn't really gone through before, which makes him sound a little differently.
DiabloFans: Now that he's so much older in the third installment of the series, did that affect how you approached his character?
Gough: Yeah, yeah, that was another thing they actually wanted too. He has aged, so he is definitely different. I'm not really at liberty to give too much away, but he sounds like he is an older version of himself.