History VideoGame / YuGiOhForbiddenMemories

** Summoned Skull with 2500 ATK and compatibility with many equip cards can be a rare example of this, if the player is lucky enough to win Job-change Mirror early in the game as a rare drop from Villager 2 or Villager 3. In this game, Summoned Skull can be summoned by fusing Job-change Mirror with ANY Fiend type monster with less than 2500 ATK (except Fungi of the Musk). If the play doesn't want to grind early for it, then they'll won't get another opportunity to get it again until midway into the game against Mage Soldier, and buying it isn't an option when it costs 999,999 Star Chips.

** For Monsters, Twin-Headed Thunder Dragon is easy to fuse into (fuse a dragon with a thunder, with one of them having at least 1600 Attack), can take a surprising amount of equip cards, and has a very powerful 2800 attack, meaning that with one equip, it gets boosted to 3300, allowing it to defeat all but four monsters in the game, and with two, it can run over everything short of a Blue-Eyes Ultimate Dragon.

* PowerUpLetdown: While Metalzoa has 400 more ATK points than Zoa does, Zoa's alignment is Mercury, which allows it to defeat the Blue-Eyes Ultimate Dragon with proper equip spells. Metalzoa loses Mercury in exchange for Mars, which is much less useful. Zoa also gets a stat advantage with the Yami field, which endgame opponents use exclusively.

** A crafty player can get mileage out of abusing the Trade system with just two memory cards, by starting a new file on their second card, trade over any useful cards from the starter deck to their main file, and then start another new file on the second card to repeat the process. This allows the player to easily get three Raigekis and valuable equip cards without having to go through the pain of S-Tecing, and load up on good fusion fodder early.

* NotTheIntendedUse: The "Trade" system allows the player to trade cards with other players given they have different save files in their memory cards. This system can be easily abused by many to duplicate rare cards (such as "Megamorph", "Widespread Ruins" or "Blue-Eyes White Dragon") by preparing three memory cards; the first memory card to play the game normally, the second memory card to store copied game data and the third memory card to store a new game with different save file for trading cards with the second memory card so the player can transfer the cards they need to the first memory card (the one they use normally).

* InfinityMinusOneSword: For equip cards, there's Bright Castle, which can be used to power up ''any'' monster's stats by 500 points.
** For Monsters, Twin-Headed Thunder Dragon is easy to fuse into (fuse a dragon with a thunder, with one of them having over 1600 Attack), can take a surpising amount of equip cards, and is a solid 2800 attack, meaning that with one equip, it can get over 3000 attack, allowing it to defeat most monsters in the end game.

** Megamorph is able to power up any monster's attack and defense by 1000 points. Having at least one in your deck is usually considered ''mandatory'' for beating the game, as the endgame opponents' cards are simply too strong to be beaten by anything else without multiple equips.
* InfinityPlusOneElement: Dragons are the game's most powerful monsters on average, having high attack and a variety of alignments, and have better fusion capabilities. This means dragons will be extremely valuable right from the beginning, and will be the player's main attacking force throughout the game. Their few downsides are a lack of equipment variety and a weakness to Dragon Capture Jar.

* AdamSmithHatesYourGuts: The max amount of Star Chips you can get winning a duel is five, and any decent card costs hundreds or thousands of Star Chips. Pocket Station-exclusive cards cost 999,999 Star Chips each[[note]]'''999,999 / 365 = 2,739.72''' which means, assuming one plays the game for one year non stop, they have to obtain '''2,740 starchips for each day'''. To unlock '''one''' card[[/note]], and you can't win them from dueling.

** Summoned Skull with 2500 ATK can be a rare example of this, if the player is lucky enough to win Job-change Mirror early in the gameplay from Villager 2 or Villager 3. In this game, Summoned Skull can be summoned by fusing Job-change Mirror with ANY Fiend type monster with less than 2500 ATK (except Fungi of the Musk). Interestingly enough, Job-change Mirror belongs to a list of top rare cards along with powerhouses such as Metalzoa and Blue-eyes White Dragon. The player either gets lucky and win the from the Villagers before dueling Seto early in the game, or they have to grind duels against top-tier opponents in the final gauntlet BossRush.

** If you attempt an S-TEC on Heishin, he can have multiples of each Exodia piece in his deck to ensure an instant win.
** The computer will swap cards during their turn for another card in their deck that is most beneficial to them. This results in the AI's deck nearly always effectively being top-loaded with the strongest monsters they have, and a useful magic card if their field isn't empty.
** During the final boss gauntlet, Heishin, [=DarkNite=] and [=NiteMare=] may look like they have 5 cards in their hand, same as you. However, when the game was datamined, it turned out that they have ''20'' at a time.

* DifficultySpike: The early game starts out easy with the exceptions of Heishin and Villager 2. Kaiba's tournament in the present has each of your opponents rapidly get stronger and more difficult. And the game [[NintendoHard never lets up from here on out]]. The BossRush in the endgame has six or seven straight duels with no save point, and every duelist has powerful monsters, spells, and traps.

** Summoned Skull with 2500 ATK can be a rare example of this, if the player is lucky enough to win Job-change Mirror early in the gameplay from Villager 2 or Villager 3. In this game, Summoned Skull can be summoned by fusing Job-change Mirror with ANY Fiend type monster with less than 2500 ATK (except Fungi of the Musk). Interestingly enough, Job-change Mirror belongs to a list of top rare cards along with powerhouses such as Metalzoa and Blue-eyes White Dragon. If the player does not have it in their starting deck, they have to grind duels against top-tier opponents in the final gauntlet BossRush for a slim chance of obtaining that card.

** Summoned Skull with 2500 ATK can be a rare example of this, if the player is lucky enough to have Job-change Mirror in their starting deck. In this game, Summoned Skull can be summoned by fusing Job-change Mirror with ANY Fiend type monster with less than 2500 ATK (except Fungi of the Musk). Interestingly enough, Job-change Mirror belongs to a list of top rare cards along with powerhouses such as Metalzoa and Blue-eyes White Dragon. If the player does not have it in their starting deck, they have to grind duels against top-tier opponents in the final gauntlet BossRush for a slim chance of obtaining that card.

*** Likewise, in TCG, [[https://yugioh.fandom.com/wiki/Skull_Knight Skull Knight]], [[https://yugioh.fandom.com/wiki/Bickuribox Bickuribox]] and [[https://yugioh.fandom.com/wiki/Labyrinth_Tank Labyrinth Tank]] are fusion monsters while in this game they are normal monsters. The players cannot fusion summon these monsters despite these respective cards' fusion materials actually exist in this game, which, again, confusing the players already familiar with TCG fusions before playing the game.

* ScrewThisImOuttaHere: In the ending of the game, [[spoiler:Priest Seto]] immediately left The Forbidden Ruins (and possibly Egypt as well) as the said person would "never to be seen again". With the amount of treasons and other heinous crimes [[spoiler:Priest Seto]] had committed, it is understandable for that person to run away in order to escape arrest.

** Summoned Skull with 2500 ATK can be a rare example of this, if the player is lucky enough to have Job-change Mirror in their starting deck. In this game, Summoned Skull can be summoned by fusing Job-change Mirror with ANY Fiend type monster (except Fungi of the Musk). Interestingly enough, Job-change Mirror belongs to a list of top rare cards along with powerhouses such as Metalzoa and Blue-eyes White Dragon. If the player does not have it in their starting deck, they have to grind duels against top-tier opponents in the final gauntlet BossRush for a slim chance of obtaining that card.

* DiscOneNuke: The Twin-Headed Thunder Dragon fusion. To create one, all that is required is any Dragon type monster and any Thunder type monster, with one of them having an attack of 1600 or higher. The Twin-Head has an attack of 2800 and is compatible with two field cards and many equip spells, making it easy to power up. With proper deck building around it, the Twin-Head can be reliably used to take on any monster outside of the Blue Eyes Ultimate Dragon, and carry the player to the endgame.

* YouMakeMeSic: Doma the Angel of Silence is misspelled as "Angle" in the card's graphic, but is spelled normally in text.

* NotTheIntendedUse: The "Trade" system allows the player to trade cards with other players given they have different save files in their memory cards. This system can be easily abused by many to duplicate rare cards (such as "Megamorph", "Widespread Ruins" or "Blue-Eyes White Dragon") by preparing three memory cards; the first memory card to play the game normally, the second memory card to store copied game data and the third memory card to store a new game with different save file for trading cards with the first memory card.

* DummiedOut: The original Japanese release of the game was compatible with the Pocket Station, with features that allowed players to obtain cards that otherwise could never be won from dueling. International releases of the game had the Pocket Station features removed, rendering said cards unobtainable without cheating.

* DittoFighter: In Free Duel, there's an opponent named Duel Master K that's available from the start, and is never seen in the campaign mode. His deck is a copy of the player's deck.

* NotTheIntendedUse: "Trade" system allows the player to trade cards with other players given they have different save files in their memory cards. This system can be easily abused by many to duplicate rare cards (such as "Megamorph", "Widespread Ruins" or "Blue-Eyes White Dragon") by preparing three memory cards; the first memory card to play the game normally, the second memory card to store copied game data and the third memory card to store a new game with different save file for trading cards with the first memory card.

* NotTheIntendedUse: "Trade" system allows the player to trade cards with other players given they have different save files in their memory cards. This system can be easily abused by many to duplicate rare cards (such as "Megamorph", "Widespread Ruins" or "Blue-Eyes White Dragon") by preparing three memory cards, the first memory card to play the game normally, the second memory card to store copied game data and the third memory card to store a new game with different save file for trading cards with the first memory card.

* NotTheIntendedUse: "Trade" system allows the player to trade cards with other players given they have different save files in their memory cards. This system can be easily abused by many to duplicate rare cards such as ("Megamorph", "Widespread Ruins" or "Blue-eyes White Dragon") by preparing three memory cards, the first memory card to play the game normally, the second memory card to store copied game data and the third memory card to store a new game with different save file for trading cards with the first memory card.

* ClippedWingAngel: [[spoiler: Zigzagged with Nitemare. On the one hand, he has no magic, trap, or equip cards in his deck, meaning once you have a monster stronger than the strongest one he has, you'll have the duel won regardless of how badly you were getting beaten. On the other hand, he does has Blue-Eyes Ultimate Dragon in his deck, which can very quickly destroy your run if you can't draw the cards needed to overpower it or remove it from the field. In fact, many speedrunners consider Nitemare to be '''more''' dangerous than Seto 3 because of his lack of magic and traps, as Seto 3 can be stalled into playing face down backrow while Nitemare will always summon high-powered monsters every turn that will relentlessly overwhelm you if you cannot quickly summon something to beat them.]]

* ClippedWingAngel: [[spoiler: Zigzagged with Nitemare. On the one hand, he has no magic, trap, or equip cards in his deck, meaning once you have a monster stronger than the strongest one he has, you'll have the duel won regardless of how badly you were getting beaten. On the other hand, he does has Blue-Eyes Ultimate Dragon in his deck, which can very quickly destroy your run if you can't draw the cards needed to overpower it or remove it from the field. In fact, many speedrunners consider Nitemare to be '''more''' dangerous than Seto 3 because of his lack of magic and traps, as Seto 3 can be stalled into playing face down backrow while Nitemare will always summon high-powered monsters that will relentlessly overwhelm you if you cannot quickly summon something to beat them.]]

* ClippedWingAngel: [[spoiler: Zigzagged with Nitemare. On the one hand, he has no magic, trap, or equip cards in his deck, meaning once you have a monster stronger than the strongest one he has, you'll have the duel won regardless of how badly you were getting beaten. On the other hand, he does has Blue-Eyes Ultimate Dragon in his deck, which can very quickly destroy your run if you can't draw the cards needed to overpower it or remove it from the field.]]