You gain the potential to deliver a powerful melee strike. If you make a successful melee strike within the spell’s duration, the target hit by that attack must make a Reflex save, or be knocked 10 feet in a direction you choose and fall prone. You can only push the opponent in a straight line, and the opponent can’t move closer to you than the square it started in. If an obstacle prevents the completion of the opponent’s move, the opponent and the obstacle each take damage as though struck by a club sized for your opponent (1d6 points of damage for a Medium creature), and the opponent stops in the space adjacent to the obstacle.