🤡 crack theory: this is out of kuroverse but hear me: undertaker was an earthbender in his previous human life who used seismic sense He got reincarnated into the kuroverse as a human,we then know that he's a reaper, he realized that he could sense vibrations from the earth and percieve the world without his glasses!That's when he started using this ability from his bender life
This is more like a 🤔, but okay. Definitely crack! Who knows what other universes interact with the Kuroverse... or what might technically exist in the Kuroverse, but we just never get to see or hear about it?
But, if your idea were the explanation, then how was Sebastian able to get around Undertaker and within the reach of his death scythe? Wouldn’t that cause vibrations for Undertaker to detect? It’s not like Sebastian was specifically trying to avoid causing such vibrations.
If you want a crack theory of mine on the subject... how about: it’s purely intuition, training/experience, and best guesses? That would explain how Sebastian managed to confuse him for a brief moment. Undertaker gets confused only when the demon thinks of something completely unexpected. Since Undertaker was also a trained reaper (and the epitome of one, to boot), he would have been skilled in the ways that reapers are generally taught to fight. He’s also got some ideas of how to fight against a lawnmower and a chainsaw.
He has to be able to quickly assess environments that are new to him, even though we know he’s clearly very nearsighted.
Yeah, my (crack?) theory is that he’s just that experienced, skilled, and intuitive.