Okay, I haven't done a review for a while. Time to take a look.
First off before the review it is important to remember this was engineered as a set not a MOC, thus crazy over the top 500 parts greebling, as much as I love that, is not the objective.
With that all said, moving on, starting with the overall shape and design of the MOC. To begin, the shape of the MOC fits both g2, the skull raider appearance, and the disfigured nature of the body as explained in the story. If I were to pick at anything in the shape, I'd say the ankle extensions being exposed draws a lot of attention, and the knee armor is pretty wide compared to the rest of the leg. Overall, the facets of his character easily attached to his physical shape in a very appealing way.
Moving on to function. Though there is nothing stunning with regards to function, the set still has reasonable ability. The torso can turn, and the limbs seem to have good maneuverability. I'm not sure if the orb is meant to be shot (I'm assuming that is the fragment of the MOUP so no) but if I'm wrong then there is one other function. Despite the lack of function the MOC definitely makes up for it with the stellar physical shape.
On to color. This set's color is probably its weakest area. Though strong colors are used, there may be too many of them. Firstly, there are all three metallics (gold trim, silver armor and gunmetal mask). Generally it is best to stick to one or two (two if you aren't using many other colors). Then there are two neutral colors, black and grey. Though there is nothing wrong with that on its own, or even paired with two metallics, with all the others, it gets to be too much. And then we have two blues. These two blues are tough to mix with even just one other color in the mix (this isn't on you, in fact LEGO barely got it to work with uniter Kopaka). While all these colors are great colors, when they're all on the same set, they clash. This creates a rather unfortunate predicament as the gold is needed for the orb, the dark blue is headed to show is unmutated state while the light blue is needed for his other half, the grey is pretty much the only color for a lot of the necessary pieces (ankle extensions and others of that type), the black seems to be a good fit for his character, the silver is better than gold for armor, and this list can go on why according to the story, most of these colors are must haves.
Anyhow, the solutions I can find have a few possibilities (though I don't think it'd be reasonable to redo it!).
First, I'd simply put more dark blue on the set. On the torso and the lower legs. Swap the black shins out for blue maybe. Meanwhile, take the gold off the body (if like the poster its on the chest, than maybe leave the chest piece gold) and let black be the trimming. This will make the gold on the staff and chest piece (if gold) pop more. Since the staff is also black, you may just do away entirely with black on the body, and rely more on blue and the metallic. Pick either silver or gunmetal to be the metallic. Though gunmetal is harder to come by, I would recommend it (I really wish the main silver armor pieces did come in gunmetal, that would make this set incredible). Silver works just as great too and likely is the better option because of how many pieces are made in silver as opposed to gunmetal, but my personal preference would have been gunmetal. With the blue and silver, you should be able to appropriately cover the body while keeping the same overall vibe (now that I'm thinking a little more, probably keep the black trimming, but only in a couple spots). As for the shape, it's all perfectly fine, and the weapons are on point. These are just my immediate suggestions. I have not constructed an Axato set to experiment with this, so I can't say I believe these suggestions would undoubtedly help. I believe they likely would, but I could be wrong
Going to the more important side of this: what I think of the set as it is. Keeping in mind this is meant to look like a set, I give Axato a solid 8.5 out of 10. The MOC has the right shape, well made weapons, sufficient functions, and an understandable color scheme that all together place it where it is on my score board.
Nice work to everyone who worked on him
On another note relating to the poster. I'm curious as to what mood, if you will, the project is going for with the visual representation of the story. The poster for Axato's instructions tells to me it is very light hearted, or at least not deeply serious. However, from what I know of the story the Bionicle Legacy Project storyline is a bit darker than that. If it was the intent to be less serious with the instructions poster, it looks just fine, but if the poster is meant to be serious, I'd recommend changing a few things such as a different font for letters, less bright highlighting/outlining of the set, and perhaps a bit of smoke/dust to ground things. That aside, like the set, it is a very nice poster.