I am always skeptical when a show decides to deviate from the source material and this show proves why.
The story was thrown away and rewritten in favor of a flashier condensed version (cannon over canon). Which is funny because the more interesting fights, events, and characters were left out of the show. A lot of this could be narrowed down to the time constraints of twelve episodes. Which begs the question of why was this even attempted? Given the success the first season had, surely a longer run time could have been done.
Art is basically the same as before.
Sound with the exception of the opening is the same. In hindsight, they should have reused the original opening. Unraveled is a tough act to follow. The chance of lightning striking twice with hit openings is very unlikely.
Kaneki's character is completely destroyed by this adaptation. The writers have hurt him more than any character ever could. It's like watching a different person.
Any enjoyment a viewer can get from this show is directly inverse to the amount of source material read.
Overall this is the worst adaptation I have ever seen. In fact, the word adaptation here is wrong. Re-imagined is more accurate.
tl;dr damn shame.
