Pretty cool movie but I would try to make a more polished looking city to make more impressive visuals.
Most people draw their cities as a series of rectangle buildings with windows and it is common mistake.
Actual cities have different kinda building structures and are extremely difficult to draw.
I would recommend looking at reference material of cities and than observe carefully while drawing.
If you live in an actual city than you have the luxury of grabbing some portable art supplies and than using the out doors as part of your reference material.
I once gone to the woods and started to look at actual trees as reference material for drawings.
It requires patience to draw from any kind of reference material.
Buildings are very hard to draw and that advice was merely a small nit pick about your movie.
I would have liked to have seen the actual helicopter getting cut by the sword.
You used the animation short cut of a darkened screen with slashes acting as colorful lights.
It's a very effective animation shortcut and I won't discourage you from using that technique.
Sometimes the darkened screen with colorful light slashes looks cool in a certain instances.
Rewatch the intro of the teenage mutant ninja turtles cartoon from the 1980's for example of a cool colorful light slashes.
Observe the part in the intro's visuals of the four turtles falling from the sky.
The turtles swing their weapons as they fall towards the earth and than finally Leonardo slashes downwards with his sword.
The screen darkens and you see leonardo's sword slash as light moving downwards.
That same sword slash also acts as a scene transition at the same time.
I'm trying to describe that very cool slash effect used in the intro of teenage mutant ninja turtles.
It's a very cool effect and you should consider borrowing it.
I liked the running cycle of the black ninja and how he leaped from one building to another.
The helicopter looked very cool and showing the storyboard used in the end credits was a nice touch.
Those were small insignificant nitpicks about your movie because the overall packaging was very cool.
You made an excellent first movie.
-Mightydein