On the first and second phrase it is purely 10/10. It is something you can't find anywhere.
On "end", i mean the final phrase as a whole, right after the Italian mission, it went sh*tty gradually as if Oku is so bored with his manga. (or he likes to troll us the reader? idk.) It is 1/10, it is a joke.
I will write more on that later,before that, this manga is so amazing. It really is a must read, so i want to write the good thing first.
The first and second phrase is pure genius. it is a must read if you don't mind blood and gore.
Many sure loves the first phrase. Me too. The first phrase is very great on plot.
The early plot is the best element on this manga, it also encourages people to follow this manga toward the end, which is also why Gantz is such a great hit.
If you read this manga without caution, the plot can be shocking, and if you put enough emotion into it, it can be sad.
That's why I can't say too much on plot for now, you should just go ahead, read it.
Oku is also talented on drawing, and of course it gets better and better over time, it is quite coherent on the final phrase,the facial expression he drew is so real. Still, can't compare the visual art of Gantz to more hardcore Berserk.
If you take the perception "manga" or "drawing" away, the visual style of Gantz is actually superior and it fits very well on its theme. Many of the "detailed" artwork,background,weapons,alien and such model from 3DCG, and then redraw by hand if necessary. Sounds like cheating,in fact,some think it looks too weird but imo, it makes the manga looks closer to the reality, more detailed and more seinen-like.
At this point i recommend you read the Osaka mission again, it is like nowhere on earth you can find manga like this one. The Italian mission is also glorious but it is very short.
Actually, the final phrase may take even more work than any previous mission but the plot is real bad,very bad. The final phrase is too Hollywood,too simple. I don't think you will have the mood to appreciate the visual side of art.
I said that the early plot is the best of this manga. In fact,it also has everything to do with the psychology of Kurono Kei, that is, the development of characters' psychology is almost equally amazing.
Gantz is about toying people between live and death, the loss and victories are absolute. It also squeezes human's emotion and doubt to the extreme. In this manga you can feel Oku's worldview of casualty, you can see good guys,bad guys,strong people,weak people...etc, while reading this manga you feel like anything can happen (it is true even after 350+ chapters...there is not even a moment you can predict Oku's act.). I know many hate this but it is essentially one of the best of this manga,imo.
Now, i review the final phrase, it is so boring i write some "big picture" so you can get the idea:
It is somewhat okay when the final phrase begins, like before, the artwork is glorious. On the first ~10 chapters it keep killing people and running and such. At first, it is endurable(at least for me) because the manga is meant to be read from head to toe, like a Hollywood movie. However, there is no end to it, it just gets more and more ridiculous, ridiculously boring, ridiculously Hollywood.
What? Tae's little adventure? With senseless plot armor? Plot armors again and again?
Now what? Introducing a series of new characters? Without any real background? In the final phrase?
Not only the plot has corruption, the 3DCG(i think he truly want it to be good) is also too unorganized, it is so unlike the previous phrase, it is so "sketchy" in 3DCG with too few elements redraw by hand, it looks so cold as a manga.
To be honest, as a reader i feel like being toyed by Oku. Nonetheless, as a reader i don't hate you, i still like your work and you.
Oku, I don't know what the hell is wrong with you but i still hope that you can finish this manga in better shape.