Every sport has its all-time greats.
For the most part, they come and they go — their longest-lasting impact is a statue outside their home arena, a number retired and a Hall of Fame bid.
In hockey, Wayne Gretzky, Gordie Howe, Mario Lemieux, Mark Messier, Jaromir Jagr (who is still playing at 44) and Nicklas Lidstrom all came and went. They dominated in their time, but none forever changed the way the game is played. The longest-lasting impact out of that group is the Gordie Howe hat trick, noted when a player gets a goal, an assist and fights someone in the same game.