Take your favorite sport. Imagine all the skills of football, rugby, soccer and baseball, then imagine them playing on ice.
That is NHL Hockey. Few sports have harder hitting, no sports have something as hard to hit/manuaever as a hockey puck (sliding on ice), moving extremely fast, all the while someone huge is trying to kill you. Then do all that while on ice, and shoot the puck in a relatively small goal. These guys are constantly going backwards, sideways, anyway at all - extremely fast with viscous contact. The most difficult footwork of any sport combined with most contact and not on solid ground.