Story: Good
Overall best isekai story yet. Revolving NOT ONLY the protagonist and his henchmen (like EVERY other isekai ever that only focus on the stupid OP-ness of it's main character while still leveling up to infinite strength) BUT ALSO involving other characters in the world (although it's just like 2 countries).
As you all that read a lot of isekai manga/novel can agree with me, isekai is power fantasy story usually showing OP MC in quest of saving the world while leveling up with it's merry harem party facing a lot of trials along the way. But unlike most isekai manga/anime, Overlord took a little bit change in the genre (if you can call isekai as it's own genre now) making it very unique and stand out compared to other isekai, which is:- making MC and the gang already OP as fuck since the beginning. This series shows only a glimpse of the power of Ainz and the gang, showing fractions of their ridiculous OP powers without any progress of leveling up. So what to do with all the powers that the MC and the gang possess? Instead of guarding the world for everlasting peace, how about conquering the world for themselves?
What make this story good? The answer is it's different with any other isekai. While most isekai focus on good-natured MC-and-friends leveling up and travelling the world to fight demon king, Overlord show the progress and how this apathetic-of-anyone-useless Demon king itself taking over the world little by little through schemes and sheer power while the humans of the worlds also got their own hidden agenda. While this show lean more to the 'serious' side, it also got bits of funny scenes that genuinely nice.
Art: Fair.
Same like any other anime production. So-so quality with generic bad CGI.
Sound: Fair.
Same like any other anime production. Nothing stand out much.
Character: Good.
Each characters in this anime are interesting. From the party of Ainz to the lowly humans, all got unique characteristic that shows how each of them suit in the scenario of each arc. From manipulating and deceiving characters to dumb-honest characters and stupid annoying characters, everyone has their own purpose.
The only thing I don't like is the lack of character introduction and their exposure for some characters. You need to read the manga and the novel for that.
Enjoyment: Good.
Very much enjoyable if you ever get sick of generic isekai with OP MC with harem of women that only revolve around ecchi things.
Overall: Good.
Can't wait for more of this anime story.
Side note:
If you are the kind that want to watch a generic isekai anime with leveling up things in term of strength and acquiring infinite new skills, new 'titles' that will never be useful for the story, with friendship power that overcome everything, fast pace, ecchi harem all episode go watch other anime. Overlord is not for you.