Libra

Woolseyism: Some of the changes 4Kids made were to the show's benefit.

• Overall, the dub's amount of sarcasm and snark is closer to the manga, where tons of characters were sarcastic and made jokes, while the subtitles are straight-laced for the most part.
• Several moments in the original anime of Tea and Tristan mocking Joey before or during duels were either cut or turned into one or both of them supporting him in the dub, which makes more sense since they're all friends. (Sometimes they kept or ramped up their teasing, but that was more in line with the original script than a significant change.)
• The dub foreshadows the fate of Pegasus's wife by having him give an internal monologue about it, which his VA Darren Dunstan delivers excellently. In the original version, it was a filler conversation between Yugi's friends and Bakura.
• In the Japanese version of the Duelist Kingdom semi-finals, Dark Yugi is dueling against Mai. He is completely focused on his duel with Pegasus, however, and doesn't take Mai seriously. She snaps him out of his funk by saying he has to beat her first. In the English dub, Yugi is holding the spirit back, as he doesn't trust it after it nearly killed Kaiba a few episodes prior, and Mai has to remind him that she promised him an honorable duel, while adding that before he can duel Pegasus he has to beat her.
• In the dub version of episode 28 of Duelist Kingdom, Pegasus plans to send Tea, Tristan, and Bakura to the Shadow Realm after they learn his secrets, explaining that the dueling rituals they discovered channel the magic of the Shadow Realm, every soul sent there increases the power of his Millennium Eye, and he needs Bakura's Ring as well as the other Items in order to have the power of life over death, so Yami Bakura stops him before harm can come to the others or his host. In the Japanese version of the same episode, Pegasus demonstrated his mind-reading powers before Yami Bakura stopped him, with no explanation for the ancient duel rituals or the cult in his basement. The same episode has Yugi's grandpa and the Kaiba brothers, pleading with Yugi to stop Pegasus for the world's sake, since his powers would be amplified even further with the Puzzle, and with all the Items he could unleash Armageddon (it's hinted that it would be by accident, which is true to canon as putting all seven Items together at this point would resurrect Zorc the Dark One). The sub had Grandpa tell Yugi he was in pain and to rescue him quickly, which doesn't explain the Kaiba brothers' presence in the vision or have the same sense of urgency.
• Pegasus' goal in the original is to recreate his wife via holograms, and to do that, he has to defeat Yugi to gain control of Kaiba Corp's technology. This made sense in the manga, but not in the anime in which he already has access to advanced hologram technology.The dub changes it so that his needing to defeat Yugi is a little more necessary: he wishes to collect his Millennium Puzzle, along with the other Millennium Items, to bring back his wife's soul and put her inside a new mechanical body rather than a hologram. While a little convoluted for what amounts to just asking him for the item, it does work, especially at the end where it's revealed that collecting the seven items does indeed open a portal to the afterlife.
• During his duel with Yugi in episode two, in the dub Pegasus talks about the Egyptian origins of Duel Monsters, including the Shadow Games and the Millennium Items. This probably intrigues Yami Yugi and helps motivate him to confront Pegasus to learn more about his past and his powers, and also provides a convenient Info Dump to set up backstory. In the original, Pegasus is just delivering exposition about the tournament Yugi is invited to, which is repeated two episodes later anyway, and the information about the Millennium Items and Ancient Egypt was given more gradually over the course of the first and second seasons.
• The duel with Bandit Keith has Marik have Keith steal the Millennium Puzzle and then duel Yugi for it, as Yugi will be a much easier opponent to defeat without the Pharaoh's help. The Japanese version has Marik make Yugi and Keith duel so he can confirm that the Pharaoh sleeps in the Millennium Puzzle and Yugi is his host, things that, between his Tombkeeper upbringing and control of Keith's mind, he already knows anyway. The Japanese version also mentions Yami Yugi staying in the Millennium Puzzle and not helping Yugi because he senses Marik watching them. Not only is this a flimsy justification for him not getting involved, but the idea that Yami Yugi could take control of Yugi's body when he's not wearing the puzzle is a Voodoo Shark that raises a lot more questions. The dub simplifies this to "their bond is too weak for them to switch places without Yugi wearing the Puzzle."
• A minor point in the duel between Joey and Odion. Odion seals the Winged Dragon of Ra in the ark on his Temple of the Kings card, then tributes Mystical Beast Serket and pays half his Life Points to summon Ra, and all of Serket's ATK points transfer to Ra. The dub makes it sound like this is an effect of Temple of the Kings, circumventing the need to tribute three monsters to summon Ra and powering it up another way since it has no Tributes to gain ATK from. Plus, this is close to how Temple of the Kings works in the real-life card game. The Japanese anime (and the original manga as well) instead treat this like a normal Tribute Summon, with Serket acting as three Tributes since it had previously destroyed and absorbed three of Jounochi's monsters. Aside from this rule being ridiculous, it begs the question of what the point was to seal Ra in Temple of the Kings and why Rishid has to pay half his Life Points to summon it, when he could have just kept it in his hand and Tribute Summoned it normally.
• Kaiba's reaction to losing to Yugi in the Battle City Finals is somewhat less immature and slightly more dignified in the dub than it was in the Japanese anime. For elaboration, see the Wangst entry above.
• The anime's take on Yugi's encounter with Ushio omits Yami Yugi beating Ushio in a shadow game and only covers the part where Yugi tries to keep him from beating Jonouchi and Honda up. As his fate is never mentioned, it ends up unintentionally implying Ushio went on to be a Karma Houdini. The dub adds in a few lines where Joey reveals that Ushio was expelled for his actions, showing that he still ended up facing some sort of punishment.
• The name Maximillion Pegasus is a plausible English name. Pegasus J. Crawford... not so much.
• "The Heart of the Cards" was something made up for the English dub, explaining that a duelist can draw the rights in a tight spot by believing in their deck and themselves and their cards will respond to that. It ended up being justified in the spin-offs where a duelist's bond with their deck gets more attention and can draw the right cards at the right times. In the Japanese version, they're hoping to get lucky and explicitly ask the "Goddess of Luck" to help them out, which stretches the suspense of disbelief when it keeps happening.