It's not Sword Art Online.

Anime about people who are stuck in an online game. Just this premise sounds very similar to Sword Art Online, but most of the anime is really quite different. The most significant difference is that people don't die in this series. The author of Sword Art Online made death a very real threat in Aincrad and some of the later arcs to make Sword Art Online a more intense and serious story, the absence of death in Log Horizon has indeed made it not as intense. In exchange, much of Log Horizon is a lot more cheerful.

Overall, any similarity with Sword Art Online is only superficial. Some people will find Log Horizon more pleasant to watch, particularly because of the many cute characters in this series.

Based on novel series of the same name. There is a second season.

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