What an Idiot!/Anime and Manga/Yu-Gi-Oh!

You'd expect: Judai's friends to agree to back off and not provide a target for the Big Bad, knowing Judai is The Ace and, with only himself going in to take care of the Big Bad, he has the best chance of doing so while cutting off the Bad's biggest advantage over him. Instead: They completely ignore Judai's pleas to this fact, dive in with him, and die off one by one as they become sitting ducks for the Big Bad. You'd Expect: Judai to pick Grinder Golem, or even Super Polymerization. Instead: He picks Mystical Space Typhoon. A card that destroys Magic cards. Such as the one that is stopping Judai from LOSING. Yubel does destroy it and Judai is in an even WORSE position. You'd Expect: Aki to activate the Dragon's effect, lower Stardust to 0, and attack for game. Instead: Aki attacks with Black Rose Dragon, lowering Stardust's ATK and doing 500 damage, but not much else. Albeit, she was trying to cause as much pain as possible, but it doesn't really get much more painful than 3000 from Aki! You'd expect: Andre to actually, you know, do so. Instead: He decides he wants to win with honor or some tripe like that. So he attacks Yusei's monster, allowing Yusei to activate an effect that wins the duel for Team 5Ds. This despite the fact that even if he had been able to destroy Yusei's monster, there was no way he could have taken out Yusei's life points by attacking, so he'd have had no option but to end his turn anyway, winning by deck out. To Make This Worse: While that was indeed idiotic, not all the blame can be put on Andre, because Team Unicorn's team strategy was, to be blunt, crap. Because Bree used a mill deck (with very little in the way of offensive cards, which is typical of mill decks), he did no damage to Yusei's Life Points at all, giving Andre (who had almost no defensive cards) a much harder job. Their team's decks (unlike 5Ds' decks) had no affinity or coherence towards each other at all, meaning no sense of teamwork or cooperation. In fact, one has to wonder if Andre's actual skills match his reputation, or if his more visible mistake was due to his assumption he'd never have to duel at all. You'd expect: The evidence against Jack here, while fabricated, seems overwhelming. Jack has never been the most stable member of the team to begin with (that old business of being a thief, kidnapper, turncoat, and almost murderer while in Satellite rarely brought up anymore...) while Red Dragon Archfiend is a unique card only Jack has access to, his Duel Runner is custom built and has a well-known design (Jack being a pro-duelist). Jack's only holdout at the moment is Officer Soichi (whose life Jack saved in an earlier episode) but everyone else - the other Signers, Ushio, and even Mikage think he's lying. The best thing the bad guys could do right now is nothing at all and one of the most dangerous thorns in their sides would be gone. Instead: The plan fails because of the android itself, in more ways than one. It's so determined to prove itself superior over the real Jack that it breaks him out of jail, simply to challenge him to a Turbo Duel to determine who is more worthy of the name. With everyone watching. Reality Ensues quickly, as it is now clear to everyone that there's an imposter Jack behind this whole mess. To Make Things Worse: Okay, there's an imposter, but how do his friends tell who's who? Well, pretty easily, actually, once the imposter summons three copies of the aforementioned unique card. Also, when seen live - as apposed to seen on camera - it becomes clear to everyone watching how unconvincing these bootleg RDAs look, as they're the wrong colors, purple, yellow, and green, as opposed to the crimson color of the real one. Eventually, Jack proves who is who beyond any doubt by summoning Majestic Red Dragon - an evolved form of RDA with divine power that the imposter could not possibly duplicate - and blows the fake RDAs and the imposter to Kingdom Come. You'd Expect: For Marik to find Odion in the ship and kill him. And if Isis tried to protect him, kill her as well (seeing how she has no Millennium Item left to defend her at this point). Instead: He just sits and waits for God-knows-how-long, and near the end of the whole thing decides to leave the airship and destroy the Deus Ex Villain's computers for the lulz. And go back on board. You'd expect: Joey would simply put monsters in defense mode. In case you didn't know, a monster in defense that's destroyed in battle deals no damage to the player's life points (with a handful of monsters having an aversion to this being their effect). It's been used before and after this duel. Instead: Joey keeps summoning them in attack mode. The monsters don't have HP like an RPG or anything, so being attacked by a weaker monster does nothing but cost yourself life points. Back when this duel took place, the rules were sort of different in a way that would have given Joey an advantage. There was no attacking directly, you could only attack as many times as there were monsters to hit. Joey could have simply put his cards on defense until he drew something strong enough to do something. Had Joey dueled correctly using the rules at the time, he likely would have only taken a total of 800 LP, out of a total (at the time) 2000. It would have kept going, but the idiot move was treated like Kaiba was genuinely skilled.
 * Yu-Gi-Oh GX:
 * It's eventually made abundantly clear that the Big Bad of the third season is specifically targeting Judai's friends and loved ones in order to inflict maximum pain on him, and will continue to target them as long as they're made a target for him/her/it.
 * Yet again when Judai is facing Yubel. Yubel has a card that allows his opponent to choose a card to put in her hand. Meanwhile Judai has finally found a way to defeat Yubel's nigh invincible monster with his overly powerful one. He equipped a magic card that allows him to bypass the ability that has caused him so much grief. So he then has to choose one of Yubel's cards to put in her hand.
 * Yu-Gi-Oh! 5D's:
 * An example from Yusei's second duel against Aki: Yusei has Stardust Dragon out and 2100 LP. Aki has her Black Rose Dragon, a Monster that can lower Stardust's ATK to 0, and an equip (Thorns of Hatred), that raises BRD's ATK to 3000, but it lowers other Monster's ATK rather than destroying them.
 * Team 5Ds vs Team Unicorn. Team Unicorn's starting duelist thrashes Jack and Aki, and does serious damage to Yusei before going down. Team Unicorn's second duelist runs a mill deck, reducing Yusei's deck to like 5 cards before going down. Andre, Team Unicorn's last duelist finds himself in the position where ending his turn would have won him the duel, as Yusei has 0 cards left in his deck.
 * In one episode of the second season, Jack Atlas is arrested for assaulting other Turbo Duelists. The evidence? Well, video footage of him with his distinctive Duel Runner and using Red Dragon Archfiend, his signature card. Jack denies his guilt, but with no alibi nor explanation, even his allies find it hard to believe him, never dreaming that, perhaps, the bad guys built an android duplicate and made a forgery of the card, which is, in facy, exactly what the Three Nobles of Yliaster have done, with the intent to frame him.
 * A more direct plot element from the first Yu-Gi-Oh series goes like this: in the middle of the ocean, the main characters' airship is attracted by a Deus Ex Villain that demands that they defeat him in a virtual reality game thing (filler, anime-exclusive arc). They do it; but by doing it they left Evil Marik, the villain, unsupervised; and Odion/Rishid, the guy he's trying to kill, at his mercy.
 * The first ever duel between Joey and Kaiba takes place at Duelist Kingdom. It's the first ever duel using the newest technology created by Kaiba Corp. Kaiba summons a fusion monster with 2000 ATK, destroying Joey's monster, and is strong enough to do so to any of the monsters Joey had in his hand.