Yu-Gi-Oh! Anime Gameplay

Duelist Kingdom Gameplay
Duelist Kingdom had a simplified card play and battle system, and is perhaps the reason why so many fans of the Anime didn't understand the TCG's far stricter rules. It had some major differences to the real life game:


 * Each player began with 2000 Life Points.
 * A few cards that are Forbidden, Limited or Semi-Limited in Real Life, were Unlimited in this Story Arc.
 * It was often inferred that only one monster could attack per turn (maybe because of the duel between Bonz and Joey), however, it was really a complicated set of rules that dictated when a player could, and could not attack because direct attacks against players are forbidden (this rule was only explained in the Japanese anime).
 * Tributes were not required to summon monsters of Level 5 or higher, so they could be directly summoned to the field.
 * Some Fusion monsters could be played directly from the hand like Normal Monsters, even if they have the violet background.
 * Machine-type monsters were immune to non-physical attacks (exept for Labyrinth Tank for reasons unknown). This rule also applied to monsters that were summoned to their favored terrain.
 * Monsters could be Normal Summoned in face-up Defense Position.
 * There is no Draw Phase on each player's first turn.
 * When a player uses a Ritual Spell Card properly, they didn't actually need the corresponding Ritual monster, which was abandoned just before Battle City. There's also debate about whether or not this also applied to Fusion monsters.
 * Each Attribute or Type had a strength and weakness against another Attribute. A superior monster will always either automatically destroy an inferior monster or lower its ATK by a certain amount (usually by 300 or returning the inferior monster's ATK to its original one).
 * If a monster was played in it's favored terrain, it would recieve a 30% increase in its ATK and DEF points.
 * All Class A Toon Monsters seen in the first season were not able to Attack Directly but were immune to attacks unless restrained (or prevented from attacking), and had to be summoned via sacrifing it's normal counterpart via Toon World's effect.
 * If a certain Trap card is Set, it automatically activates if it meets its requirement for activation. The controller has no control when this happens.
 * If a monster is Summoned in Attack Position, that monster must attack that turn if possible, usually because that's the point of summoning it.
 * Some Normal Spell cards could be activated during the opponent's turn.
 * Monsters can't Direct Attack.

Battle City Gameplay
Battle City more accurately represented the real rules of the card game, but it still had some differences as follows:


 * Each player began with 4000 Life Points.
 * Fusion Monsters could not attack in the turn they were summoned. Players had to instead use the card Quick Attack, to allow the Fusion monster to attack in the turn that it was summoned. After Battle City, this rule was eliminated.
 * When a Fusion Monster was Tributed, it was treated as a number of Tribute Monsters equal to its number of Fusion Material Monsters.
 * Example A: Seto Kaiba tributed 1 XYZ-Dragon Cannon to Tribute Summon Obelisk the Tormentor.
 * Example B: Yugi used Marik's Egyptian God Slime as 2 Tributes to activate the effect Of Obelisk.
 * Spell cards could be used on the opponent's turn if they were Set, even if they weren't Quick-Play ones.
 * Monsters could still be Normal Summoned or Tribute Summoned in face-up Defense Position.
 * Many Effect Monsters had yellow backgrounds as if they were Normal Monsters. However, some of them still had their effects (such as Big Shield Gardna and Legendary Fiend).
 * The "Amazoness" cards had their names shortened to "Amazon".
 * Direct Damage Spells such as Hinotama and Ookazi are forbidden (this was only explained in the Japanese anime since Joey used Hinotama in the Friends Til the End part of Battle City.)
 * It was infered you could discard cards any time you wished for effects, such as for Spiritualistic Medium. In the real game, you can't discard when you want to, you need a card effect that requires you to do so.
 * If the number of monsters on the field changes during a Battle Phase, no replay is conducted.

Most of the Battle City rules were basically the same ones used for the remainder of the series as well as in Yu-Gi-Oh! GX.

Virtual World

 * Many monsters had their own abilities when they were used as a "Deck Master". For more information, see Deck Master Abilities.

Yu-Gi-Oh! the Movie: Pyramid of Light

 * Class A and B Toon monsters were Normal Summoned instead of Special Summoned.

Waking the Dragons

 * Toon monsters were much more accurate to the Current TCG rules in this season, but they were still immune to attacks from non-Toon monsters.
 * It seems that if you're participating in Tag-Team Duel, you can still activate cards that affect your partner even after you officially lost the duel. This was proven when Yugi and Seto faced Dartz because Seto activated Wish of Final Effort after his Life Points hit 0.