The Super Nova special clears all letters from the board. Points are scored for all letters on the board.
Like the Super Nova in the wild, this special explodes upon activation, clearing away everything in its path with its shock front.
You get points for every letter on the board when you activate one of these specials. Therefore, try and fill the board with as many chips as you can before you activate one of these bad boys in order to maximize your points.
Hint: the Super Nova special is the fastest way to win a Clear the Board game.