Too short!
There is no sense in having a fight if you don't show some action... where is the big battle of this scene? All I saw was ninjas that appeared to want to have sex with that dog!
I'm giving you a 1/10 for your attempt, but, yeah, it could be longer. Your animation is pretty basic as well, try some fbf (frame-by-frame) and that would give the animation a pretty cool effect.
Nice try, but, sorry, only 1/10 from me.