Though the manga is now over and the anime is close behind, Attack on Titan is still one of the biggest anime franchises in the world. Helping to usher in a new wave of horror-infused shonen manga, the series has more than left its mark as it steadily expanded into a franchise.

Lesser-known is the fact that Attack on Titan was also inspired by another multimedia anime franchise: Muv-Luv, specifically, Muv-Luv Alternative. A visual novel series that expanded into a massive multimedia franchise, one which continues to evolve, what Muv-Luv lacks in notoriety it more than makes up for in influence. Now that a new anime adaptation is on the way, here's how the mechs vs. aliens franchise inspired Hajime Isayama.

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The Story of Muv-Luv Alternative

The Muv-Luv franchise started in 2003 with the release of the eponymous visual novel. It was a fairly traditional romance focused around a character named Takeru, who wakes up to find a beautiful young woman in his bed as his childhood friend Sumika discovers them together, kicking off a love triangle. Takeru learns that the young woman was a rich heiress named Meiya who he's supposedly meant to marry, with the conclusion of the story determined by which woman he chooses to be with.

The second part of the game is where things become far less traditional, with Takeru awakening in an alternate version of his reality. This is a planet besieged by alien invaders, where mecha are sent to the front lines to combat the extraterrestrial threat. The aliens have killed off an overwhelming majority of humanity, with those who remain fighting a fierce struggle for survival. From there, the series branches out to a parallel set of Earths, with Takeru no longer sure which reality is the true one. Originally released for the PC, the various parts of the story were eventually brought to the Xbox 360, PlayStation 3 and PlayStation Portable.

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How Muv-Luv Inspired Attack on Titan

Eren _ Mikasa _ Rico _ Ian _ Garrison Elite Squad _ Attack on Titan

The similarities between Muv-Luv Alternative and Attack on Titan are fairly obvious. Both take place in a world that has been absolutely ravaged by non-human destroyers, though the Muv-Luv's attackers are alien invaders while Attack on Titan's are gigantic, man-eating Titans. The grunts of each species also operate in a similar way, being unthinking, lumbering brutes that can be taken down with the same method every time.

Eren Yaeger's personality is also similar to Takeru's, as they both possess anger brought on from PTSD caused by their traumatic lives. In Takeru's case, however, this personality builds up after living through the game's various parallel Earths. They even begin to resemble each other more and more once Eren takes on a darker, more disheveled appearance.

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The armies of both series also highlight the depressing and tragic nature of both, as many of the soldiers end up dying throughout the course of their respective series. This is made even sadder by the fact that the majority of them are developed and well-rounded characters, turning the inevitable slaughter into an exercise in tearjerking.

In a bit of full-circle twist, the two franchises have actually crossed over in the past. Muv-Luv Alternative: Strike Frontier was a browser and later mobile game that held an Attack on Titan crossover event, with the Titans having to face gigantic robots and aliens of their own height. Muv-Luv predates Attack on Titan by a little over a decade, and Hajime Isayama has made it clear that it was an inspiration for him. While it may not have gone on to be nearly as popular as what it influenced -- hardly anything is -- Muv-Luv's legacy continues to be felt in the anime industry as the franchise continues to grow.

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