Log Horizon had a huge amount of potential. It had moments of greatness alongside plenty of slice of life moments. There was playing around with cliches and using them in surprising ways. The second season shows just how much the staff actually hate the viewers.
The second season of Log Horizon is an exercise in masochism. Like many viewers, I have this obsessive streak which makes me want to finish what I started vieweing. Boy do I regret it. It caused me not only to despise every moment of the second season, but to also retroactively start loathing the first. It is like they used every single trick to make the show less appealing and fun.
A common complaint about the first season is that things move too slow and that there is too much fluff in Log Horizon. Of course, the second season slows the pace down to a crawl and manages to be far more fluffy. But no, it isn't even the good kind of fluff where it is light hearted fun, or cheerfully romantic, or philosophically deep. Any of those would be fine, and in the first season we had a surprising amount of that. The fluff of the second season is the type where the characters are dumbed down in order for their interactions to fit the emotional range of twelve year olds.
Log Horizon manages to be insulting to the viewer on many levels. From an intellectual perspective, the first season had the whole "integrating off-line and on-line personas" theme, which no longer exists. From a philosophical perspective the first season had "where is the border between real and virutal if you cannot escape the virtual", so naturally the second season ignores that. From an emotional perspective the first season had characters learning to cope with a strange world whose rules changed, and in the second season that is replaced with the cheapest form of interpersonal drama. The writing staff thinks so lowly of the viewers that I cannot help but feel insulted not only on my behalf, but on that of the people surrounding those arrogant bastards.
Writing (Story and Characters):
Good lord did someone drop the ball here. The writing staff deserves not only to be fired, but to be whipped in the town square. I'm not sure how they managed to take all of the potential of the first season and miss every drop of it. Was it intentional? Did they try to be this bad? Did they take the guy responsible for all the good stuff and chain him in the basement? These questions are really the only ones left that I want answered about Log Horizon.
A story that goes nowhere seems to be the "idea" behind the second season of Log Horizon, and if that was what they wanted, well, misery accomplished. There is literally one main plot that they hint at, and in eighteen episodes there is nothing that manages to actually move it forward. Not one damn thing. The "plot" at this point becomes nothing more than a hindrance. While it is not the worst concept, the attrocious execution, pacing that ranges between a snail's pace and outright going nowhere, and character driven elements that are all but futile make this one of the least enjoyable stories in recent anime.
My main problem with the first season of Log Horizon was that the cast was too big to actually develop in a meaningful way. So naturally, the way to solve that was to dumb down the characters and stop whatever development they had in its tracks. What was an average cast has been turned into a bunch of characters that elicit no empathy from the viewer and manage to drag down whatever character-driven elements there are to the story down. Whatever potential there was in the first season is so carefully taken out of its place and shot in the face, and then peed on.
Very rarely does someone manage to fail as badly as the writing staff of Log Horizon did in the second season. It has the "irrelevant OVA" feel as the centerpiece, and instead of picking up and giving the depth that seemed to be lurking in the first season there is absolutely no redeeming feature to the writing of the second other than the fact that memories remain of when it was better. Fire the staff. Every single one of them. Or whenever someone has a suggestion, do the exact opposite. These are the only solutions I can find for this catastrophe.
Artwork (Animation and Sound):
Not that it was particularly strong in the first season, but the artwork manages to become even worse in the second season of Log Horizon. it isn't so much that the animation changed, nor that the sound changed. It is more of the same. Only we now get one crappy amateur song that is repeatedly shoved down the throats of all viewers.
Usually a second season learns from the mistakes of the first and manages to build an even more compelling visual world. After all, the basic concept art has already been drawn, the character designs are already there, and all that is needed is to sharpen things up. Naturally, none of those things happened in Log Horizon. The animation still remains exactly the same, no more impressive and no less. Some points for style, but others removed for mediocrity.
Sound was perhaps the strongest point of the first season of Log Horizon and the second season does exactly the same. Perhaps I haven't explained how annoying that one song is that they think is supposed to show us how awesome one of the characters is. They managed to take the most generic song ever, and give it uninspired lyrics and bad vocals. This is supposed to wow us. Do they really think the viewers lack any taste?
While the artwork is generally the better part of Log Horizon's second season, it doesn't manage to live up to the modest success of the first. A bump in quality here could have made the world feel more alive, bit instead, it was like the staff didn't even try. Somehow, that is even more insulting than being bad.
Overall:
Don't watch it. Just don't. If you enjoyed the first season, leave it at that. Do not repeat my mistake and allow Log Horizon to defile what little interesting things existed in the first season.