A vintage cartoon from 1937 called Swing, Monkey, Swing sounds remarkably similar to the theme used for Sonic when he drowns.
Ask any Sonic player what the most unnerving thing in the series is, and they'll likely all give you the same answer - drowning. Not just because drowning is scary enough in and of itself, but because of a special jingle that plays when Sonic is running out of air, one that slowly builds up a distinct beat and high-pitched noise more and more until Sonic dies.
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The drowning theme is synonymous with Sonic the Hedgehog and has appeared in pretty much every game in the series, even making a brief cameo in the latest film. The sound has become so iconic that Sonic fans are even hearing it in things long before the hedgehog's time. Twitter user RecDTRH was watching old vintage cartoons after playing Cuphead and came across a Columbian one from 1937 called Swing, Monkey, Swing, and immediately noticed how similar it sounds to Sonic the Hedgehog's drowning theme.
RecDTRH said, "Cuphead got me watching a lot more vintage cartoons but this one made me do a double take when I found it because ITS MAIN MUSICAL MOTIF IS THE SONIC THE HEDGEHOG DROWNING THEME". The video they shared alongside the claim shows several scenes from the animated short, all of which have a beat that sounds exactly like Sonic drowning, just a little deeper. Watching the full clip shows that the beat isn't always there, but when it is it's unmistakably similar.
It's clearly a much deeper beat than the one seen in Sonic, which gets higher and higher as you get closer to death, but the resemblance between the two is uncanny. Sonic fans then compared the two side
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