Ray Liotta.

Robert DeNiro and Joe Pesci were better in Casino, and should've won for their performance in that. In Casino, they were the main characters, and you went deeper into their minds. Goodfellas was just the same thing but less for them.
DeNiro's quiet, smart tough guy persona and Pesci's crazy tough guy image were both aggraded and performed to the max in Casino, along with different sides to their personality.

All other Ray Liotta's movies were just 90 % medicore Hollywood action movies. Goodfellas was his best performance ever. Narc was his second best and a damn good movie. Cop Land was also good.

After I saw the bedroom scene were Ray's wife held a gun to his head, that did it for me. It was his movie. I don't know if he should've won an Oscar, but he should've been nominated.