Before he got to the NBA, Artis Gilmore had built a reputation at Jacksonville and in the ABA as a mobile and effective big man.
At Jacksonville, he teamed with Pembroke Burroughs to form one of the first twin towers in college basketball - Gilmore was 7-2 and Burroughs 7-0.
And in the ABA, he was the best big man the league had ever seen.
This video is more oriented to show skills than most similar retrospectives are. You can see here that he has a nice hook shot and a nice jump shot among other refinements to his game.