Saturday Twelve is a side-scrolling beat'em up game produced by MurderGames, a brazilian indie game development studio. Saturday Twelve is scheduled to be released in 2013 for Windows PC.
The spin attack is a special move that can hit multiple enemies within a certain range. It's very useful for when you see yourself surrounded by enemies or even as a devastating counter attack in case you get hit.
The use of the spin attack requires some strategy though. Every time you use it, you will drain your stamina bar. If you use the spin attack while your stamina isn't 100% full you will lose a small amount of health.