The aum version work by having a trail model with a lot of quad polygon interconnected, then set their vertices using interpolation results between the first quad and the last quad(or atleast that what I think grin )

Mine work like how particles work. I create a quad-polygon entity with the 1st & 2nd vertices set to the current sword's vertices, and the 3rd & 4th using the last sword's vertices. I create it every two frame (though it can be set into every frame but will create more trail). The trail fades away using alpha and removed when it's alpha reach 0.

BTW, I think I'll sign up to be beta tester grin