The Sword Art Online: Progressive light novels, a highly popular retelling of the original Aincrad arc, are getting an anime adaptation. Like the original series, Progressive is authored by Reki Kawahara, with six volumes published so far and translated into English via Yen Press. A teaser trailer for the upcoming anime shows Asuna in civilian clothes and giving a short monologue.

Many SAO fans unfamiliar with Progressive will be asking similar questions: How is this different from the original series? Does it contain crucial details that were previously left out? Most importantly, will it be worth tuning in to find out? Let's take a look at what Progressive is all about and why many fans of the novel series say it is what the Aincrad story was meant to be all along.

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At its core, Progressive is the original Sword Art Online arc told in far greater detail. The premise remains the same: Kirito is one of 10,000 gamers trapped within the VR game Sword Art Online. If they die in the game, they'll also die in real life. Here, Kirito and Asuna's adventures span every single floor of Aincrad, each one vastly different from the last while presenting unique new challenges and compelling new characters never seen in the original anime. Some characters, such as Kizmel, will be familiar to those who have played SAO video games such as Hollow Fragment or Hollow Realization.

The general pacing is quite a bit slower, with more time spent exploring the various areas of each floor from castles to lakes to dungeons and sand dunes. One floor is even made up entirely of puzzles. It's also worth noting that, through the six novels published so far, several characters from the original arc have not yet been introduced. Lisbeth and Silica, for instance, are nowhere to be seen, though Agil and Klein -- both of whom Kirito met on the first floor -- are here. Others such as Argo the information broker and the origins of the player-killing guild Laughing Coffin are given more time to develop their place in the story.

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Yuuki and Kirito from Sword Art Online.

Perhaps the biggest reason many fans prefer the Progressive version of the Aincrad arc to the original is the evolution of Kirito and Asuna's relationship. Instead of falling in love over two novels or a few episodes, here their friendship (notably not yet a relationship as of Volume 6) develops much more gradually. Asuna remains untrusting of Kirito for a while and keeps him at arm's length, but as the two open up and get to know each other on a deeper level, hints of romantic feelings begin to emerge. Of course, being SAO, the two get themselves into a few comedically awkward situations that end with Asuna hitting Kirito for something he did on accident. It all feels true to the original characters while giving their bond a deeper and more natural progression than before.

The Sword Art Online: Progressive novels have been well-received by longtime fans because they strike the balance between giving a more in-depth, floor-by-floor account with innovative new ideas and characters while remaining true to the original tale. Some of the more divisive parts of the original story -- awkward pacing, Kirito's aloofness -- are ironed out while each floor contains its own unique setting, adventures and challenges. The upcoming Progressive anime is absolutely worth adding to watch lists for longtime fans as well as newcomers, and may even be worth another look for those who weren't fans of the original.

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