Designed by Norman Foster, this 2006 skyscraper is dramatically different than any building built at the time. And I think it broke the mold for how skyscrapers should look. No more or at least less regular grids of verticals and horizontals in NYC high rise. Now, more glass, with twists as the building rises or changes in massing.
The Hearst Tower sits on a six story base (in the shadows) built in 1928. It has been described as Art Deco,but it is at least as much fortress like.