Duel Monsters (also known as Magic & Wizards) is a card game introduced in Yu-Gi-Oh! manga. It was a card game that revolves around players using "Monsters" and "Spells" to decimate their opponent's Life Points and win a duel. It is introduced in Chapter 9 of the manga.
The rules is modified overtime, as the manga becomes more engage in using the card game as the medium in doing duels and battles. Here are some of the listed rules.
This is the rule first presented in Chapters 9, 10 and 37.
- 1. Each of the two players prepares a 40 card deck to play.
- 2. They each have 2000 Life Points and have 5 cards at the start of the game.
- 3. The players each take turns in drawing a card from their deck and deciding whether to attack or defend.
- During each player's turn, they may lay one "Monster Card" in either "Attack" (vertical) or "Defense" (horizontal) position.
- 4. When a player attacks:
- ATK > ATK (of attacked monster in waiting): The attacked monster is killed and the defending player loses LP based on the difference.
- ATK < ATK: The attacking monster is killed and the attacker loses LP based on the difference.
- ATK = ATK: Both monsters are destroyed. No LP loss.
- ATK > DEF (defending monster being attacked): The attacked monster is killed. No loss in LP.
- ATK < DEF: No death and the attacker loses LP based on the difference.
- ATK = DEF: No death and No LP loss.
- If the defending player has no monsters, the attacking player can attack their LP directly.
- 5. "Monster Cards" can have abilities, which can affect the outcome of a battle.
- 6. In addition to "Monster Cards" there are also "Magic Cards", which can affect both player's cards.
- If a Magic Card is played downward, the player does not have to reveal it until it is used. 
- 7. The first player to lose all their LP is the loser.
Standard (Duelist Kingdom)Edit
This is the rule presented when the in-story creator of Duel Monsters, Pegasus J. Crawford, was introduced in the the manga. In addition to special abilities, elements also becomes crucial when battling monsters in the game.
- 1. The players start with 2000 Life Points each. Each prepares a 40 card deck and draw 5 cards to start the game.
- 2. Each player takes turn using "Monster Cards" and "Magic-User Cards" to try and reduce their opponent's Life Points to zero. A player draws 1 card from his/her deck per turn.
- 3. When two "Cards" fight, the difference in ATK points is subtracted from the Life Points of the Losing Player.
- 4. The Cards that lose are sent to the "Graveyard."
- 5. Some Cards may be used in combination with others to make "Combos".
- 6. Monster Cards and Magic-User Cards may become weaker or stronger based on their target's or opponent's "element."
- Magic-User Cards have 4 elements: "Black Magic", "White Magic", "Demonic" and "Illusionist". The strengths of each elements are: "Black Magic" > "White Magic" > "Demonic" > "Illusionist" > "Black Magic".
- Monster Cards have 5 elements: "Water", "Wood", "Earth", "Lightning" and "Fire." The strengths of each elements are: "Water" > "Fire" > "Wood" > "Earth" > "Lightning" > "Water".
- 7. Monster Cards and Magic-User Cards may become weaker or stronger based on the playing field's "element."
- In Duelist Island, there are 5 landscapes which compliments each of the Monster Card's elements: Sea (Water), Forest (Wood), Wasteland (Earth), Mountains (Lightning) and Grassland (Fire).
- 8. In addition to the Monster and Magic User's element, and the playing field's landscape, abilities of each Monsters and Magic Users in battle can also affect the battle's outcome.
- 9. A player can fuse monsters using "Fusion" and summon a new monster.
- 10. A new monster can be summoned using a Ritual Spell Card. One monster of Light and one of Darkness must be sacrificed.
Expert (Duelist Kingdom/Duel Disk)Edit
This set of rules are given during Seto Kaiba's introduction of Duel Disk in Duelist Kingdom. While it modifies some of the rules from the Standard Rule, the other rules still apply.
- 1. Each player starts with 2000 Life Points and 5 cards in hand.
- 2. Only 5 cards can be used at a time. These cards are fitted onto the Duel Disk.
- 3. There are 2 stages that the cards can occupy:
- Main Card Stage: Holds the Main "Monster Card" to battle. Can either be placed in "Attack Position" or "Defense Position." The duel disk projects the main image of the card placed on this stage.
- Sub-Card Stage: Holds the rest of the 4 cards. These appears as cards on the projection. These can act as support for the main Monster Card. Main Monster Card can attack these cards directly (face-up or face-down), with either destroying the target card automatically or forcing the support monsters to battle. Monster Cards placed on this stage cannot receive support from any cards, except by their own effect.
- 4. On the start of a player's turn, the player draw as many cards from his/her deck if necessary to maintain using 5 cards in play.
Super Expert (Battle City)Edit
This new set of rules was introduced during Seto Kaiba's Battle City Tournament. New set of card, called Trap Card, is introduced. Tribute Summoning is also put in place. Any of the rules from Standard Rules that does not conflict with the new rules can be used.
- 1. Each player starts with 4000 Life Points.
- 2. Each player's deck must contain 40 cards.
- 3. When the game begins, each player draws 5 cards from their decks.
- 4. A player can either play a Monster Card, a Magic Card or a Trap Card on his/her turn.
- 5. When a player's Life Points reach zero, that player loses.
- 6. When a player cannot draw a card from their decks anymore, that player loses.
- 7. A Monster can either be played on Attack Position (face-up vertical) or Defense Position (face-up horizontal).
- 8. When attacking:
- Attack Vs. Attack: The monster with higher ATK wins. The losing monster is destroyed and the difference in points is subtracted from the losing player's Life Points.
- Attack Vs. Defense: If the attacker's ATK is higher than the defender's DEF, the defending monster is destroyed. The defending player loses no Life Points. If the attacker's ATK is lower than the defender's DEF, the attacking player loses Life Points equal to the difference in points.
- In Super Expert Rules, monster may attack the enemy player if the player has no monsters to defend with.
- 9. Monsters with five or six stars may only be summoned by sacrificing one of the player's other monsters. Monsters with seven or more stars may only be summoned by sacrificing two of the player's other monsters.
- 10. Magic Cards can be played face-up or face-down during the player's turn. The face-down Magic Card can be activated at any time.
- 11. Trap Cards need to be played face-down first before activation. It can only be played the next turn after it was set. A certain condition is needed to trigger its activation.
- 12. A player can fuse monsters using "Fusion" and summon a new monster.
- A player can treat the Fusion monster as many as the monster cards used to Fusion summon it.
- 13. A new monster can be summoned using a Ritual Spell Card. One monster of Light and one of Darkness must be sacrificed.
- ↑ The starting 5 cards is never mentioned in the rules when the Duel Monster Game was introduced in Chapters 9 and 10, but was used during the game. It was elaborated in Chapter 37.
- ↑ This step is elaborated in Chapter 37, but was already in use in Chapter 10.
- ↑ This part is never mentioned in any rules, but implied during the battle in Chapters 37, 39 and 40. Early Monster Cards with abilities are "Winged Dragon, Guardian of the Forest" and "Exodia the Forbidden One".
- ↑ This part is mentioned in Chapter 10.
- ↑ This part is mentioned in Chapter 10.
- ↑ "Monster Cards" and "Magic-User Cards" can only attack cards. They cannot attack a player directly, with the God cards being exception to the rule.
- ↑ The term "Magic-User" refers to Magicians or Spellcasters.
- ↑ Choosing either "Attack" and "Defense" positions for "Monster Cards" and "Magic-User Cards" in play still apply.
- ↑ A player can also set a "Monster Card" or "Magic-User Card" face-down. It can be revealed when an opponent declares an attack or fulfills a certain condition.
- ↑ The previous rule on a battle between attacking and defending combatant cards still apply.
- ↑ Priorities in attacking applies in battle. Usually, the one who initiate the attack has the initiative to attack first.
- ↑ The Cards refer to "combatant" Cards, the Monster and Magic-User Cards.
- ↑ Some battle enhancements (to ATK and/or DEF) from a Combo only works when the "combatant" hits the opponent/target. If the "combatant" has not hit its target and lose, its base ATK and DEF points are used instead in battle calculations.
- ↑ A "combatant" Card is not necessarily restricted to being a Monster or a Magic-User. "Summoned Skull" has both elements "Demonic" and "Lightning", making it both a Monster and a Magic-User.
- ↑ One consequence of having a Card fight against an opponent possessing an advantageous element (i.e. Fire against Water) is having the former's ATK points halved during the battle.
- ↑ A "combatant" Card played on a field of its element has its ATK and DEF point increased by 30%.
- ↑ A "combatant" Card played on a field of its element, in contrary to its opponent, has the initiative to attack "first".
- ↑ For examples, a flying Monster has an advantage over those who cannot fly; A sea creature can hide underwater and attack those over the water undetected; etc.
- ↑ 19.0 19.1 While a player can fuse any monsters, monsters that have incompatible elements (e.g. Water fused with Fire) can result in an unstable fusion monster. One consequence is for the fused monster to reduce its ATK and DEF until it completely disappeared.
- ↑ 20.0 20.1 The fusion materials stays on the field, representing the Fusion monster as there is no "Fusion Monster Card" in the story.
- ↑ 21.0 21.1 In some cases, sacrificing an additional monster, with attribute and element close to the Ritual Monster intended to summon, is needed.
- ↑ A player can decide not to put a card on the Duel Disk. However, the card(s) in hand is still counted on the 5 card requirement to play.
- ↑ Images from a support card are also projected when the owner plays the card.
- ↑ Cards that directly support the Main Monster Card are not removed from the play after used.
- ↑ A trap Card can be triggered sometimes, considering conditions are met.
- ↑ Hidden Monster Cards are shown during battle
- ↑ In English version, 40 cards is listed as minimum number. However, characters in the manga stress that exact 40 cards are needed.
- ↑ Magic Card is same as real game's Spell Card.
- ↑ In English version, it is stated that this only happen when drawing a card during the start of a turn. However, circumstances in the manga shows that inability to draw a card at any time means losing the duel.
- ↑ In real game, a player has to set the Monster Card in face-down horizontal position from hand to play it in Defense Position.
- ↑ In the English version, it is noted that the attacking monster is destroyed if loses against a defending monster. This is not true.
- ↑ God Cards need three tributes to be summoned.
- ↑ Some monsters have the ability to fuse without the need for "Fusion"
- ↑ e.g. Fusion monster that is summoned with fusing 2 monsters can be used as a sacrifice by itself to Tribute Summon a level 8 monster.