Most of the X is really Y ones, any of the A+J ones, X+A=D/J, Bolt-on, are the ones I could think of off the top of my head.
Okay, what is wrong with Bolt-On? I mean, it is 100% fake, but it is a pretty fun theory and is a cool way of doing vampires in Westeros. And since the Starks are pretty much werewolves, it fits!
I get that it started very much tongue-in-cheek, but it became emblematic of the over-ferment in some corners of the fandom where people started arguing for OTT theories just because they were novel.
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