It is my habit to go straight to the point and I hope readers can forgive me if this review lacks the often poetic and fancy language found in other "professional" reviews.
One-Liner:
Horrible, a total let down to the Shadow Skill saga.
The Good:
I wish there was something redeeming in this anime, but...
The Standard:
#1 Voice Acting - Reasonable with a few quirks. Ellie's voice sounds too demure, not the kind of voice you would expect from a martial arts master.
The Bad:
#1 Animation - There's way too much emphasis on 3D CGs that are very poorly rendered. The lack of details and motion is appaling, it's like watching a fixed 3D generated scenairo with a couple of camera pannings. For a martial arts anime, it's quite ridiculous to have people talking all the time with minimal background movements.
#2 Cut Corners - The show utilises a kind of "impressionist" technique for flashbacks. What we have is one red coloured background with a few shillohutes conversing. That's how all the flashbacks are presented and trust me, there's way too much of these scenes for a short movie. I see this as laziness of the production team rather than some form of artistic expression.
#3 Sound - There are no more than 3-4 tracks for the entire movie. Except the opening which is mildly pleasing, the remaining tracks are indistinguishable. Due to a lack of tracks, there are way too many scenarios that either go without bgms or have totally inappropriate music that damages the mood.
#4 Story - Bad guy steals a key and proceeds to unlock a secret move at a secret place. Good guys go there to stop him and secret move gets destroyed for good at last. Sounds simple and lame? Yep, that's all there is to the plot - There are no sub plots, no build up, no mysteries, no romance and remarkably, very little fighting.
#5 Character - Absolutely no effort has been put into the characterization. All we have are a few poorly done scenes about how Gau's parents were killed and how he struggles with his dormant hatred. Oh did I mention that this is all done in the red + shillohutes technique I explained earlier?