A funny thing I noticed a few months ago is that the majority of modern anime series has theme songs that are roughly 90 seconds in length. So, one day, I was watching an anime with a theme song I didn't particularly care for, so I decided to mute the opening theme and play a different theme song while watching the opening. Surprisingly, the visuals matched up almost perfectly!

Ever since then, I've tried many different combinations with different themes overlaid on different opening sequences. Some were decent, some didn't match up well at all; however, others were either too funny or too fitting to keep to myself.

This first video is the first opening sequence to Keroro Gunso/Sgt.Frog with the opening theme, "Guren no Yumiya," from Attack on Titan. I may upload more eventually, but I encourage you to try mixing up a few for yourself. You may come up with something I never would have.

Invasion of the Demon Frogs

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Got a couple of new ones...

The first one is the first opening sequence to Fullmetal Alchemist: Brotherhood set to the second opening theme, "Ready Steady Go!," from Fullmetal Alchemist (2003)

http://flic.kr/p/w1Ytdm

And the second one is the second opening sequence to Fullmetal Alchemist (2003) set to the first opening theme, "Again," from Fullmetal Alchemist: Brotherhood.

http://flic.kr/p/vLDsSA


(Note: I apologize for these not being on Flickr instead of YouTube (mainly because of the lack of fullscreen), but YouTube kept muting the audio).

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Ouran High School Host Club mashed with Attack on Titan. It's incredible.

https://www.youtube.com/watch?v=zTgI3yjEwr4

And the other way around:

https://www.youtube.com/watch?v=fWkMjiXFl_g

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