Hmm...pretty nicely done for a first timer's work. The "Nyx" reminds me of Sasuke's Chidori a bit xP. The action was okay, but the enemies are...magic glyphs, I suppose? Is it even possible to destroy/stop floating drawings?
Hmm...the "true" battle scene was a tad boring, but it was nonetheless quite well done for newb work. The girl was....wayyyy too stacked, in my honest opinion. And it felt like she was brainwashed or something, if she didn't care about him the same way, and attacked ruthlessly.
This is pretty good, but would be disappointing if you are just gonna leave it like that. Some graphic improvements are needed, especially the special effects, concentrate on those first, as you've probably been told of millions of times. You should also try more on the liquid, like the water and blood. They look like simple squigly lines instead of actual fluid.
Finally, please add a sequel. This work really needs one, for questions(too many) unanswered.
And by the way, what's the name of the chick's Dual Arms? I'm just dying to know. Mmmm...blade-type weapons....nice....