To beat the boss at wave 14, hit his blades back at him. Just use the level 2 weapons and aim right at them and they will fly back at him and kill him and allow you to kill him.
WARNING!!!!!!!!!If you have not beaten the end this is a giveaway!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
At the end,When he is back near his grave,He learns that he is already dead.Its kinda hard to explain.
Vote up if you think this is a great Flash.But,this should NOT be a 4 story series.Once I read a 4 story series,It was so bad I barfed on the 3rd book.