Sean Monahan had a hell of a sophomore season. After his breakout rookie year, many were expecting him to regress; instead, he became a 30-goal scorer. He also nearly doubled his rookie point totals, jumping from 34 to 62. Injuries thrust him into a first line centre role, and he took to it pretty much immediately.
Once he was put in between Johnny Gaudreau and Jiri Hudler, that was pretty much it: an absolute force of a line, composed of absolute forces of players, was born.
There was something else going on with Monahan, though. It took him a while to get going, leading to sophomore slump speculation, but when he got going, he really got going.