In order to be the victor of a Tower Battle, you must have the most points out of all the other players after all 5 matches/Time Runs out.
In order to get the most points, you'll need to win fights quickly with minimal damage and preform a finisher.
Extra points can be earned if you complete each individual match challenge ex.(Land 4 front punches and win the Round) (Win a round with out Front Dashing), and a multiplier on said extra points for consecutive challenge successes.
If the other players quit during the match, or you end up alone, just keep playing until you reach the end, even if you are the only player the win will still count!
After winning your first Tower Battle you will unlock this Trophy.