William Sadler, who has had roles in The Shawshank Redemption and Hawaii Five-O but who may be best known for his role as the Grim Reaper in Bill & Ted's Bogus Journey, is reportedly in talks to take a role in Iron Man 3, according to a rumor at Latino Review.
Latino Review isn't always right when it comes to stories like this (they were the ones who claimed G.I. Joe: The Rise of Cobra had been taken out of the director's hands during editing), but they've got a pretty good batting average and even with a Die Hard 2 pedigree, Sadler still isn't a "sexy" enough target for a fabricated story to seem likely.
The site reports that yesterday when actor Guy Pearce was on-hand for his wardrobe fitting, he was seen walking around with Sadler. From that, they conclude that Sadler was also there for a wardrobe fitting, although it's unclear at this point what character Sadler might play. They also note that it seems unlikely Sadler would play a villain, as there are already three of them on hand that we know of, and speculate that Coldblood-7 and Firepower might not even "suit up" in this installment of the series.
Sadler recently made news when he announced that he may be in line to reprise his role as Death from Bill & Ted's Bogus Journey in the upcoming Bill & Ted 3, which has been written but not yet greenlit.