My idea for the demoman is that the demoman would go in a dbz like powerup stance and his eyes would flame then he would throw the blade up in the air slightly*since its spinning it will have damage effect on the person infront of him* and he will then punch it with his bare hand making it go forward and slicing the enemys head off.. when he goes in the power stance he'll make a bull sort of noise
i just came up with this lol