Amaterasu...

I think that it should be used by clicking on the ground.
Maybe u should be able to use it a few times(maybe5?) and then it gets on cd.
And the flames should auto move another or two tiles towards the closest enemy.

I tihnk it shuld fallow your mouse cansor, like moving with mouse as it be easier to aim. I would also say to make Amarterusu like toggle, you use it once and you create amarterusu as till you press jutsu icon again. It would be more cool.