Yu-Gi-Oh! is a card game that has an anime and manga series to help promote the game. Before Sevens, the Booster Packs would often contain cards used by a character from one of the Yu-Gi-Oh! anime/manga series. Over the years, many cards were adapted from the anime/manga. Sometimes the cards are buffed, sometimes they are nerfed... However, sometimes they just have their effect changed completely. This article will look at the cards whose card effects (or even Card Type) changed completely when being adapted to real life.

Aria the Melodious Diva

OCG: While this Special Summoned card is on the field, "Melodious" monsters you control cannot be targeted by card effects, or be destroyed by battle.

Anime: Once per turn, when your opponent does not take any battle damage from an attack involving this card: You can inflict 800 damage to your opponent.

The adapted version of this card turned the card from an offensive attack card to a defensive stall card. In a way, this card is partly responsible for turning the archetype from an aggro deck (depicted in the anime) to a field control stall deck. It also had a significant impact on the archetype's design. It's clear from the get-go that Konami wanted the OCG Melodious version to be played with pendulum monsters.

This card also clashed with some of the later Melodious supports. For example, Solo the Melodious Songstress' second effect of Special Summoning a Melodious monster from the deck is difficult to trigger due to Aria's battle protection effect. Aria also prevents some effects from certain support cards like Fortissimo, Melodious Illusion and Canon the Melodious Diva. 

Elemental HERO Stratos

OCG: When this card is Normal or Special Summoned: You can activate 1 of these effects.
● Destroy Spells/Traps on the field, up to the number of "HERO" monsters you control, except this card.
● Add 1 "HERO" monster from your Deck to your hand.

Manga: You can halve this card's ATK until the End Phase to allow this card to attack your opponent directly this turn.

The change to Stratos is interesting. In the manga, it was a monster that could attack directly by halving its attack. However, the real-life version turned Stratos into a searcher and Spell/Trap remover.

Stratos went from a worthless card to a staple card in HERO deck in its adapted form. For the longest time, this card was banned due to its easily abusable search power. To this day, people still runs Stratos thanks to the utility it provides. 

Meklord Emperor

OCG: All the Meklord Emperors are a single monster that can be Special Summoned when a card is destroyed on the field. 

Anime: The Meklord Emperors comprises smaller parts of one giant monster. Each piece has its own individual effects. 

Both the anime and adapted Meklord continues the gimmick of being an anti-synchro deck. However, the playstyle is entirely different. The anime also had additional gameplay to power each piece to grant more effects. In contrast, the real-life version has all the ' effects crammed into one monster.

The OCG version is better as the pieces don't clog up the entire field, enabling the player to use other monsters. In saying that, the OCG version also have effects nerfed compared to the individual piece's effects from the anime

Card of Sanctity

OCG: Banish all other cards you control and in your hand (min.1 from each); draw until you have 2 cards in your hand.

Anime: Each player draws until they have 6 cards in their hand.

The changing of this card in adaptation is understandable as the anime version would've just been broken. Imagine setting your entire board turn 1 and then playing this card to refuel your hand again for more shenanigans. The real-life version nerfed the drawing power and gave it a very steep activation condition.

This card went from a 'benefit me' card to a 'benefit the opponent' card. It is hilarious that this would've been a staple card in every deck had it kept its anime effect. Now, it's a card that only gimmicky decks use. 

Masked HERO Dark Law

OCG: Must be Special Summoned by "Mask Change". Any card sent to your opponent's GY is banished instead. Once per turn, if your opponent adds a card(s) from their Deck to their hand (except during the Draw Phase or the Damage Step): You can banish 1 random card from your opponent's hand.
Manga: No effect

Similar to most manga HERO cards, when Dark Law was adapted to the OCG, it was changed completely. Its artwork received a significant update. It was also changed from a vanilla monster to an effect monster. The OCG version was given two extremely good effects (banishing all cards sent to the GY and banishing a random card if the player searches).

The OCG version of Dark Law kept HERO relevant for many years thanks to its anti-meta effects. To this day, people still end their turn on Dark Law, which shows how well this card has aged. 

Nirvana High Paladin

OCG: 1 Tuner + 1 or more non-Tuner Synchro Monsters
For this card's Synchro Summon, you can treat 1 Pendulum Summoned Pendulum Monster you control as a Tuner. If this card is Synchro Summoned using a Pendulum Summoned Pendulum Monster Tuner: You can target 1 card in your Graveyard; add it to your hand. When this card destroys an opponent's monster by battle: You can halve your opponent's LP. If this card in the Monster Zone is destroyed by battle or card effect: You can place this card in your Pendulum Zone.

Anime: You can Special Summon this card (from your Extra Deck) by Tributing 1 Synchro Monster and any number of Pendulum Summoned Pendulum Monsters, whose total Levels exactly equal 10. (This Special Summon is treated as a Synchro Summon.) When this card on the field is destroyed: You can place this card in your Pendulum Zone.

Nirvana High Paladin is an interesting card. It's a Synchro Pendulum monster (hybrid) with a lot of hype surrounding its debut in the anime. However, when it was quickly destroyed the next turn, many people were confused by how anticlimactic it was. That is because the anime Nirvana High Paladin is really just a vanilla monster when summoned onto the field. The OCG team gave Nirvana High Paladin actual monster effects, such as recovering cards from the grave and halving the opponent's LP. Its Pendulum Effect of both the anime and OCG versions are relatively the same, so that's one thing. The anime version is just a card waiting to get destroyed, while the OCG version is an actual boss monster. 

Red-Eyes Darkness Metal Dragon

OCG: You can Special Summon this card (from your hand) by banishing 1 face-up Dragon monster you control. You can only Special Summon "Red-Eyes Darkness Metal Dragon" once per turn this way. During your Main Phase: You can Special Summon 1 Dragon monster from your hand or GY, except "Red-Eyes Darkness Metal Dragon". You can only use this effect of "Red-Eyes Darkness Metal Dragon" once per turn.

Anime: This card cannot be Normal Summoned or Set. This card can only be Special Summoned by Tributing 1 "Red-Eyes Darkness Dragon" equipped with "Metal Plus". This card gains 400 ATK for each Dragon-Type monster in your Graveyard. You can negate the effect of Spell Cards that target this card. You can discard 1 card to negate the activation and effect of any Spell Card your opponent controls and destroy it.

Red-Eyes Darkness Metal Dragon is such a good card. It is a true staple for every Dragon-Type decks as it can easily Special Summon itself onto the field, and it's a free Monster Reborn. However, the card is nothing like the anime version at all. Everything was changed from the artwork, summoning conditions and even effects. The anime version's summoning condition requires the player to tribute a Red-Eyes with Metal Plus equipped. It then sits on the field and negates any spell cards the opponent uses by discarding a card. Ignoring the summoning condition, both versions are actually pretty good in their own right. The anime version is more of a boss monster that you end your turn on, while the OCG version acts more like an extender to further continue your combo. 

Windwitch - Winter Bell

OCG: You can target 1 "Windwitch" monster in your GY; inflict damage to your opponent equal to that target's Level x 200. During the Battle Phase (Quick Effect): You can target 1 "Windwitch" monster you control; Special Summon 1 monster from your hand with a Level less than or equal to that monster, but it cannot attack this turn. You can only use each effect of "Windwitch - Winter Bell" once per turn.

Anime: Once per turn: You can target 1 Level 4 or lower "Windwitch" monster in your Graveyard; until the end of this turn, this effect becomes 1 of that monster's effects.

Windwitch is an archetype that debuted in the Arc-V anime. It had an interesting gimmick where the boss monster doesn't have actual effects of its own. Instead, it copies the effect of the smaller members in the archetype. Now in the anime, we only got to see one Windwitch duel. In that duel, we only got to see the character using Winter Bell's effect to copy the burn effect of Windwitch - Snow Bell. Therefore, when this card was adapted to the OCG, its effect changed completely from copying the monster's effect to simply "inflicting burn damage." Winter Bell was also given the effect to Special Summon another Windwitch from the hand to reference the anime spell card, 'Call of the Windwitch.'

The changes were probably made because Konami has no intention of making Windwitch a full-fledge archetype. In fact, when it was first adapted to OCG, the Windwitch was created as a mini-engine to get out Crystal Wing.

The Seal of Orichalcos

OCG: All monsters you control gain 500 ATK. Once per turn, this card cannot be destroyed by card effects. While you control 2 or more face-up Attack Position monsters, your opponent cannot target your monster(s) with the lowest ATK for an attack. If this card is activated: Destroy all Special Summoned monsters you control. You cannot Special Summon monsters from the Extra Deck. You can only activate "The Seal of Orichalcos" once per Duel.

Anime: This card increases the ATK of its controller's monsters by 500. This card's controller can Summon monsters in their Spell & Trap Zones, which cannot be attacked unless there are no monsters in their Monster Zones. This card's controller can move monsters from their Monster Zones to their Spell & Trap Zones. This card cannot be destroyed by card effects.

The Seal of Orichalcos is a spell card that debuted in the DOMA arc in the first Yu-Gi-Oh! Series. Its significance to the plot is comparative to similar plot cards like "Super Polymerization" and "Earthbound Immortals. where it symbolizes that the controller has descended down a dark path. Being such an important card that took years to be adapted to real life, you'd think it gets to retain most of its original effects when it was adapted. However, that didn't happen at all. The OCG version lost the ability to summon monsters in the Spell/Trap zones or move monsters to the Spell/Trap Zones. It also has its protection effect nerfed. However, the OCG version gave the card a battle target effect and it nukes all Special Summoned monsters you control. It's possible that the whole summoning onto the Spell/Trap Zone is a ruling nightmare, so they just opted that out. 

Flame Swordsman

OCG: Flame Swordsman is a Level 5 vanilla Fusion Monster. 
Anime: Flame Swordsman is a Level 5 vanilla monster.
Manga: Flame Swordsman is a Level 6 vanilla monster. 

Flame Swordsman is such an iconic card. When people think of Joey, Flame Swordsman is usually one of the monsters used to represent his deck. Despite being an iconic card, the OCG version adapted the Flame Swordsman into a Fusion Monster. To be honest, all iterations of Flame Swordsman are horrible. Still, if it was just a plain vanilla monster like in the anime or manga, the player can summon this monster easily. I honestly can't think of a single reason why this card was changed into a Fusion Monster. Maybe they thought Fusion Summoning it will be easier than Tribute Summoning it?