Since we're on the subject, of Yu-gi-oh, I always wondered, by the time the lead cast went to the island (this was the first season), were none of Yugi's friends aware of his alter ego? I remember watching the dub and while I don't remember exactly who Yugi was dueling, they were pretty far in, and Yugi transformed into Dark Yugi multiple times already in front of his friends, and the the girl suddenly notices that Yugi acts differently and is taller some times. I wasn't sure if it was a dumb dub mistake or what.
Also, the manga is infinitely better than what we got in the anime (either dub or the original). When did it turn into a shitty card game?
In the manga he didn't get any taller, his voice didn't transform, in general he didnt change that much physically. He just got silently possessed which caused him to hold himself differently and stand up straighter, have a more confident look in his eyes, and speak with more authority. The "change" did get exaggerated over time though to make them look more different from each other. At the beginning they looked basically identical except that one looked totally maniacal.
The japanese anime followed a little more closely to this but modeled itself after the later more chill Pharaoh. Usually the puzzle would very briefly glow with a soft "ding" sound and suddenly Atem would be in the house.
However the english dub consistently edited in the big transformation sequence to make it more exciting and gave him a deep ass voice, which makes it puzzling why nobody seems to notice right away. A guy just went fucking super saiyan and Anzu is all like "oh that's ever so slightly peculiar." Meanwhile Kaiba is standing around wondering "Why the fuck is nobody seeing what I'm seeing?!" No wonder he had an even larger stick up his ass in the dub.
I believe the manga didn't go full card game until volume 8. That's where Duelist Kingdom starts, which is where the anime picked up. Then it's all card game up until volume 32 where it backs off from it a bit and goes to Egypt for the final few volumes. Pre-8 and post-31 are actually my favorite parts of the manga though I do enjoy later Battle City as well.
He got away with way worse stuff in that arc in the manga. The anime cut out the cast having to ascend the entire tower, which was a gauntlet of deathtraps disguised as amusement park attractions. A roller coaster ride where they were strapped to electric chairs that would activate if they made a sound, "laser" tag with professional assassins, and a haunted house a genuine chainsaw-wielding serial killer. The entire secondary cast was along for all of this too. All of this so that Kaiba could challenge Yugi to a card game. Of course, it was revenge for their previous encounter where Yami-Yugi trapped Kaiba in a horrible nightmare of being eaten by duel monsters that left him with serious mental scars. He created the hologram system just to replicate that effect on Yugi and give him a taste of his own medicine.
The manga was messed up.
This makes me want to read the manga again. Dark Yugi running around making people experience their own personal hell until they go insane. Good times.