There are 3 important terms to fully understand the Yu-Gi-Oh! Game Mechanics. Those are action, reaction and priority.

Actions are:

• Setting a card.
• Summoning a monster.
• Declaring an attack with a monster.
• Frist draw in a turn.
• Manually changing the battle position.

You cannot chain to an action, as actions do not posses any Spell Speed. Therefore, you can only answer to an action with a reaction. Fulfilling an action does not pass priority, so the turn player has still the chance to react to his own actions first.

A reaction is the answer to an action. Because you cannot chain to an action, we simply call it "to react". In conclusion, we only use the term "reaction" when we want to activate something in response to an action to differ it from "chaining".

Basics regarding priority:

Priority describes the right of a player to activate a card or an effect and to do an action respectively. Everytime a player has no priority, it simply means he has to wait for his opponent do do something. Always remember that priority changes between both players, so that both players have the chance to do something in turns.

What does priority comprise of?

Basically, the Turn Player is always the one having priority first. He can use his priority or pass priority to his opponent, which means he gives his opponent priority to do something. The opponent now may also choose between using his priority or passing it.

A Turn Player may use his priority to activate a Spell or Trap Card. If the Turn Player decides to Summon a monster, he is the first player to get priority. Theoretically, he is the first one that may negate the Summon of his own monster. If he does not want to negate his own Summon (that is most likely), the non-Turn Player gets priority to negate the Summon with cards like "Solemn Judgement". If the non-Turn player does not want to use his priority and passes it back to his opponent, the monster is successfully Summoned.

As a non-Turn Player, you can always only activate cards and effects that can be activated in your opponent's turn. When a player uses his priority to activate an effect or card, he automatically passes priority to his opponent. Now, the opponent may decide to activate an effect or card.

You ALWAYS need priority if you want to do anything.

Priority in Chains:

If a player uses his priority to activate a card's effect, this effect starts a chain. Afterwards, his opponent gets priority to chain (use priority) or pass. If both players pass one after another, the chain starts to resolve in reversed order (see chapter "Chains"). After a chain resolved, it is always the turn player getting priority to react to the last resolved effect.

Retaining Priority:

As already explained, priority changes between both players in turns. But this does not count for actions. If a player does an action, he retains his priority.

Always keep in mind that the Turn Player has only a limited priority after a Summon. He cannot summon another monster right away. Afer doing an action, a Turn Player`s priority is limited to the following 2 options:

• activating the Ignition Effect of a Monster (! ONLY after a successful summon!)
• activating an effect with Spell Speed 2 or higher.

If a Trigger Effect controlled by the Turn Player activates due to the successful Summon (e.g. Zaborg the Tunder Monarc), the priority is automatically used for this Trigger Effect.

How to handle Priority:

Of course you can always ask your opponent if he wants to use priority or not. But it is much easier when the player that wants to use priority simply states when he wants to. For example, it might be helpful to state directly when summoning: "I use my priority to ..."

This also counts for the non-Turn Player. If the non-Turn Player wants to activate an effect in Main Phase 1, but the Turn Player immedatly declares an attack after summoning his monster, you can say: "After you passed priority (and this is what the Turn Player did to change into Battle Phase), I activate ...".

You might already note that it is really important to communicate properly in order to avoid problems. Of course, you cannot use this method to dodge something. Players are always responsible for a clear Game State and might get penalties if not caring for it.

Concrete Examples:

Player A Normal Summons "Snipe Hunter". As the Summon is an action, player A retains priority to activate an Ignition Effect of a monster (e.g. "Snipe Hunter") or to activate a Spell Speed 2 or 3 card (e.g. Torrential Tribute). After player A used or passed his priority, player B can choose to react to the action.

• If player A uses his priority to use the effect of "Snipe Hunter" or another monster, the priority automatically passes to the opponent afterwards.
• B can chain to the effect of "Snipe Hunter" (e.g. with "Skill Drain").
• B can react to the summon with a suitable card (e.g. "Trap Hole").
• If A DOES NOT want to use his priority to use his "Snipe Hunter`s" or another monster's effect, and also does not want to react with a Spell Speed 2 or higher effect, this means he passes priority to his opponent.
• B may now react to the action of A (Summoning of a monster).
• If B now activates "Trap Hole" or "Torrential Tribute", "Snipe Hunter" cannot be chained to this as it is an Ignition Effect (Spell Speed 1). He gets destroyed in the resolve.

Player A (Turn Player) Normal Summons "X-Saber Airbellum" in his Main Phase 1. He does not use his priority and declares a direct attack with "X-Saber Airbellum".

• B can still activate "Threatening Roar" as A never declared his change from Main Phase 1 into the Battle Phase. For this, he would have had to pass priority to B first, meaning that B would have had activated "Threatening Roar".
• The Game is rewinded to the Start Step (last thing both players agreed to) and Player A cannot attack during this turn.

Mostly in the Standby Phase, the End of Battle Phase or the End Phase, it might happen that several effects need to resolve, but there is no exact time stamp when these effects need to resolve. Therefore, we resolve these effects following the principle of priority and NOT after SEGOC.
In the easiest case, a player controls all effects that need to be resolved in the same Phase. This player may choose the order in which he wants to resolve those effects.

Example:

Player A is in his Standby Phase and controls a "Messenger of Peace" and has a "Treeborn Frog" in his graveyard.

• Player A may choose which effect he wants to resolve first.
• Therefore, he may first choose to not pay the Mainentance Costs for "Messenger of Peace" so that the card is sent to the graveyard.
• Afterwards, Player A can Summon "Treeborn Frog".

This concept gets a bit more complicated if both players control effects that need to resolve. Because the Turn Player has priority, he may choose to use one of his effects or pass priority. If he activates an effect, both players will proceed with building a chain as usual. After resolving that chain (remember: Even if it is only 1 chain link, it still is a chain), the turn player again gets priority and can activate the next effect. Only if he passes his priority, the turn player can activate one of his remaining effects (or something else). If the Turn Player does not want to pass priority, he can first activate all effects that need to resolve in this specific Phase.

Example:

Player A attacks with his two "Gladiator Beast Laquari" into his opponent's two "Gladiator Beast Hoplumus".

• At the End of Battle Phase, player A may first activate both his "Laquari" monsters and resolve them. Only after this (or if he passes priority), B may activate his "Gladiator Beast Hoplumus'" effect.

If there is a mandatory effect involved, and both players pass priority, the Turn player MUST activate one of his effects (else, we would be in an infinite loop). After this happened, and no one wanted to chain, the effect resolves and the procedure starts again. The turn player has now again the priority to activate an effect or to pass priority.
If the Turn Player controls no more mandatory effects, the mandatory effects of the non-Turn player have to resolve. In conclusion: In case of mandatory effects, if the non-Turn player chooses to pass priority back, the Turn Player has to resolve his mandatory effects first.

At a Tribute Summon, there are different kinds of effects that can be activated when the monster is summoned:

• Mandatory Trigger Effects that trigger upon tributing, e.g. "Sangan".
• Optional or mandatory Trigger Effects that react to the Summon, e.g. "Mobius the Frost Monarc" or "Zaborg the Thunder Monarc".
• Ignition Effects of face-up Monsters you control or that are in your graveyard, as long as they are chain link 1.
• Quick Effects without activation requirements, e.g. "D.D. Crow".
• Also, different permanent Effects and Effects from Spell and Trap Cards, as well as cards that react to the activation of an effect may influence.

How these are resolved is explained in the following chapter. To understand it, you should have read the chapters about "SEGOG", "Monster Effects" as well as "Action, Reaction and Priority".

Depending on the Level of the Monster that should be Tribute Summoned, 1 or 2 Monsters are needed as a tribute. If those tributed monsters posses a mandatory Trigger Effect (e.g. Sangan), their effects trigger right now and are to be put first on the chain after the successful Tribute Summon. Optional Trigger Effects (e.g. "Jinzo Returner") miss their timing when used for a Tribute Summon, because they need to be activated RIGHT NOW and therefore cannot be activated later on. When several monsters with mandatory Trigger Effects are tributed, they go on chain following SEGOC. When the Monster is successfully tribute summoned, we first look if there is an effect that negates the effect of the Tribute Summoned monster (e.g. "Skill Drain"). If this is not the case, the permanent effects of the monster are immediately active. Now, all other permanent effects on the field are counted in. After this, all Trigger Effects that need a successful Tribute/ Normal Summon trigger (e.g. "Mysterious Puppeteer", "Caius the Shadow Monarch") go onto 1 chain.

Now, all Effects that triggered until now form a chain and are therefore activated. Effects of the tributed monsters and effects that trigger upon a successful summon are NOT combined to into one chain together using SEGOC. First, all graveyard effects chain following SEGOC, then all effects that trigger upon the successful summon are chained using SEGOC. The reason for this is that both kind of effects trigger at differend times.

Optional Trigger Effects like the one of "Mobius the Frost Monarc" can also be activated if they are not chain link 1. The reason for this is that those effects trigger upon a Game State that is not changed when building the chain and therefore they can also be activated at a later time.
Important: These effects have to be activated at the next possible time. Else, the effect counts as not activated and even if the Game State does not change, they cannot be activated later on.

Example:

"Sangan" is tributed for "Mobius the Frost Monarc" and becomes therefore chain link 1 after the successful Summon.

• The effects do not form a chain using SEGOG, therefore, the Monarc should have missed timing. But the effect triggers to the Summon/the Game State.
• After "Sangan" becomes chain link 1, that is the only time where the optional Trigger Effect of Mobius can be activated, so the effect becomes chain link 2.
• If the player does decide to not use the effect of "Mobius", he cannot activate the effect later on.

After all triggering effects went onto the chain, the player whose effect is not the last one in the chain gets priority.

Ignition Effects (e.g. "Exiled Force", "Snipe Hunter") can only be activated if they are chain link 1. The reason for this is that Ignition Effects always need to be chain link 1.

As soon as the opponent has priority, he may use it either to chain to the effect last activated in the chain or to response to the Summon (e.g. "Torrential Tribute").

Examples:

"Skill Drain" is face-up on the field. A tributes "Treeborn Frog" for "Jinzo".

• After "Jinzo" is summoned, we look for permanent effects that might negate "Jinzo".
• Because "Skill Drain" is already face-up on the field, the continous effect of "Jinzo" is negated.

"Goblin Zombie" is tributed for "End of Anubis".

• First, "Goblin Zombie" is sent to the graveyard and triggers, but his not activated right away.
• "End of Anubis" is now summoned. Because there is no effect negating his permanent effect, the effect becomes active.
• The effect of "Goblin Zombie" activates now, but is negated by "End of Anubis" in the resolve, because the effect activated in the graveyard.

"Level Limit - Area B" is face-up on the field. "Jinzo Returner" is tributed for "Horus the Black Flame Dragon LV6".

• "Horus the Black Flame Dragon LV6" is summoned and we look for effects that might negate his effect.
• Because there is no negating effect, the effect of "Horus the Black Flame Dragon LV6" becomes active.
• Because of his effect, "Level Limit - Area B" has no effect on "Horus the Black Flame Dragon LV6", he remains in ATK position.
• "Jinzo Returner" has an optional Trigger Effect and therefore misses the timing when used for a Tribute Summon. The Game State is incorrect for his effect.

Now, some more advanced examples:

Player A tributes "Sangan" and "Treeborn Frog" to summon "Dark Magician of Chaos". B controls a "Mystic Plasma Zone" and a "Mysterious Puppeteer".

• "Dark Magician of Chaos" is successfully Summoned. As there are no effects that negate his effect and he himself has no permanent effect to negate, all other permanent effects are calculated in.
• The ATK of "Dark Magician of Chaos" is increased by 500 due to "Mystic Plasma Zone" and his DEF is reduced by 400.
• Now, the effect of the tributed "Sangan" activates and the mandatory Trigger Effect of B's "Mysterious Puppeteer" becomes chain link 2. The optional Trigger Effect of "Dark Magician of Chaos" can be activated as chain link 3. ("Sangan" has been chain link 1 because he triggered earlier, chain link 2 and 3 form a chain following the principles of SEGOC.)
• After this, the opponent gets priority, because it is A's card that is the last chain link. B can now response to the summon or chain to the effect of "Dark Magician of Chaos". In our example, both players pass priority.
• Resolve: Chain link 3: A adds the Spell Card targeted by "Dark Magician of Chaos" from his graveyard to his hand. Chain link 2: The Life Points of B are increased by 500 due to "Mysterious Puppeteer". Chain link 1: "Sangan" searches a monster from the deck.

Important: When a monster is tributed for a Tribute Summon and the effect of the monster triggers (e.g. "Sangan"), the effect of the tributed monster has to be chain link 1. Even if the Tribute Summoned monster has also an effect (e.g. "Caius the Shadow Monarc"), the effect is then chain link 2, as the trigger for "Sangan" was earlier.

Player A tributes "Sangan" for "Zaborg the Thunder Monarc". "Final Attack Orders" and "Stumbling" are face-up on the field.

• "Zaborg" is summoned and all permanent effects are counted in. Because "Zaborg" is already in face-up ATK position, "Final Attack Orders" has no influence on him right now.
• "Sangan" triggers as chain link 1. The mandatory effects of "Zaborg" and "Stumbling" trigger to the Game State "Zaborg is successfully summoned". "Zaborg" as mandatory effect of the Turn Player becomes chain link 2, the non-Turn Player's "Stumbling" becomes chain link 3.
• Now, A has priority as B's effect is the last one on the chain. Because no one wants to respond or add a chain link, the chain resolves.
• Resolve: Chain link 3: "Stumbling" turns "Zaborg" into Defense Position. Right after the resolve of this chain link, the permanent effect of "Final Attack Orders" turns "Zaborg" back to Attack Position. Chain link 2: "Zaborg" destroys the targeted monster. Chain link 1: "Sangan" searches an appropriate monster.

With the aid of "Soul Exchange", Player A tributes his opponent's "Goblin Zombie" and his own "Sangan" for "Light and Darkness Dragon". Player A also controls a "Mysterious Puppeteer" and B has a face-up "Stumbling".

• "Light and Darkness Dragon" is summoned. Because there is no effect negating it, his permanent effect becomes active, he is now both the Attribute LIGHT and DARK.
• First, the effects that triggered when sent to the graveyard form a chain following SECGOC: The Turn Player's "Sangan" becomes chain link 1, the non-Turn Players "Goblin Zombie" becomes chain link 2.
• Now, A`s "Mysterious Puppeteer" gets chain link 3, B's "Stumbling" gets chain link 4 following SEGOC.
• Only now, the mandatory Quick Effect of "Light and Darkness Dragon" activates and chains to the LAST chain link. Now, the effects are resolved in reversed order.

The term "Game State" is inofficial and no futher explained in official ressources. Still, the Game State plays an important role in comprehending certain Game Situations.

The Game State describes what happens just now in the Duel. Even if there is nothing happening at all, the Game State says exacly this. We call this a "neutral Game State". Generally spoken, only during a neutral Game State a player has the opportunity to play cards from his hand. Examples that need a neutral Game State: Normal Summon a monster, do an inherent Special Summon, activate a Normal Spell Card, set a Trap Card, ...

The Game State changes due to actions and the resolve of effects, e.g.:

• Card(s) drawn
• Attack declared
• Summon (Normal, Special, Flipp)
• Card set
• Card destroyed
• Card added to hand
• Control changed
• Neutral (nothing happens right now, player has full priority)

Remind: The Game State does not change during a chain.

Example:

Player A summons "Destiny Hero - Dasher" using his priority on neutral Game State. The Game State changes from "neutral" to "monster summoned". A has a set "Torrential Tribute" and B has a set "Bottomless Trap Hole".

• A passes his priority so that B can activate his "Bottomless Trap Hole". The activation is legal as the activation restriction of "Bottomless Trap Hole" meets the Game State.
• A chain starts, but the Game State is still "monster summoned". Because of this, A can activate "Torrential Tribute". The chain resolves: All monsters on the field are destroyed and "Bottomless Trap Hole" resolves without effect.
• The Game State changes to "card resolved without effect" as this was the last chain link that resolved.

The last thing that happened during a resolving chain is the new Game State until both players pass priority. If Player A passes priority, Player B can use his priority to respond to the game state. If B does, A can choose to chain to B's response or respond himself to the Game State.
To return to a neutral Game State, both players need to pass priority after the resolve of a chain or an action one after another on an empty chain.

Example:

A Summons "Destiny Hero - Dasher".

• The Game State changes from "neutral" to "monster summoned".
• A has now priority. He passes it.
• Now, B has priority. He also passes it.
• Because both players passed priority one after another, and there is no effect on a chain, the Game State changes back from "monster summoned" to "neutral".

Every time the Turn Player enters into a new Phase, he has priority. If he wants to enter the next Phase, he has to pass priority first. This means that the non-Turn Player gets the opportunity to activate a suitable effect before the game continues in another Phase. Only when both players pass priority on a neutral Game State, the game continues into the next Phase. Therefore, there is no thing like "react to the change of a Phase", it is simply the prioriy the opponent automatically gets when the Turn Player wants to enter a new Phase. After entering a new Phase, the Game State is still neutal, the turn player has priority.

Example:

Player A controls a face-up "Pitch-Black Warwolf" that was summoned the turn before. He wants to enter the Battle Phase. To do so, he passes priority on an empty chain on neutral Game State. B activates "Enemy Controller" and changes "Warwolf" into Defense Position.

• Because B did not pass priority, the Phase did not change. The game is still in Main Phase 1.
• As A's "Warwolf" was not summoned this turn, A changes its Battle Position back to Attack Position. After entering the Battle Phase, he can attack.

"Manually" means to change the Battle Position without an effect. The player simply uses a general Game Mechanic to change the Battle Position of his monsters once per turn. But there are restrictions. The change of a Battle Position is only possible when:

• The Battle Position of the monster has not already manually been changed this turn.
• The monster has not been summoned by the Turn Player this turn.
• The monster did not attack until now this turn. (If it attacks after the manual change of the Battle Position, that is ok.)

If one of these 3 criterias is not met, you cannot manually change the Battle Position. Also, the change of Battle Position can only be done on neutral Game State.

Examples:

Player A attacks with his "Cyber Dragon" a set "Morphing Jar #2". The Flip Effect of "Morphing Jar #2" resolves and Player B Special Summons 2 monsters in face-down Defense Position. Player A has a "Mind Control" on his hand.

• A may use his "Mind Control" in Main Phase 2 to take control of 1 of B's set monsters.
• Because the monster was not summoned by A, he can now manually change the Battle Position of this monster. He can Flip Summon the monster.

Player A's "Stealth Bird" is flipped face-up because of an attack. It is A's turn.

• A can set "Stealth Bird" by its own effect.
• Afterwards, A can manually change the Battle Position of "Stealth Bird" because there was no manual change in this turn.
• It is not possible to use the effect of "Stealth Bird" to set it again face-down this turn because its effect was already used this turn.

A attacks directly with "Spirit Reaper". B responds with "Scapegoat".

• A replay occurs. A decides to stop his attack.
• A cannot change the Battle Position of "Spritit Reaper" because it declared an attack this turn.

There is no limit to the number of times a monster's battle position can be changed by card effects.

Examples:

Player A flips his "Stealth Bird" and attacks with him.

• A can use "Stealth Bird's" Effect to set him face-down during Main Phase 2.
• Even after an attack, the Battle Position of a monster can by changed by an effect.

A flips his "Needle Worm" to use his Flip Effect. Afterwards, he uses "Book of Moon" to set him face-down again. Following this, he activates "Book of Taiyou" to flip "Needle Worm" again.

• Even though the monster's Battle Position was already changed manually AND by an effect, it is possible to change the Battle Position again by an effect.
• Theoretically, A may activate even another copy of "Book of Moon" and "Book of Taiyou".

There are some card effects that forbid the change of a monster's Battle Position (e.g. "Thousand Eyes Restrict"). Those effects generally only prevent manual changes of the Battle Position, a change by a card effect is still possible.
It is still possible to change the Battle Positions of face-up monsters with level 4 and higher while "Level Limit - Area B" is active. The monsters are simply changed back to Defense Position afterwards.

A set monster has NO type, attribute, level, ATK or DEF. Also, it has no name and no effect. A set monster is simply a set monster.

Example:

A has a set "Spear Dragon" and a face-up "Lord of Dragons". B activates "Nobleman of Crossout" and targets the set "Spear Dragon".

• "Lord of Dragons" cannot prevent "Spear Dragon" from being targeted by "Nobleman of Crossout" because a set monster has no type.
• "Spear Dragon" is banished by "Nobleman of Crossout".

But it is possible to tribute a set monster as a cost for another card as long as the set monster fulfills the requirements.

Examples:

• A tributes a set "Treeborn Frog" for "Spiritual Water Art - Aoi".
• A tributes his set "Jinzo" for "Deck Devastation Virus". He can do so because he as the controlling player sees that his "Jinzo" meets the requirements. Also, "Jinzo" is never face-up, so the Trap Card can be activated.
• A plays "Book of Moon" on his opponent's "Jinzo". Afterwards, he wants to use "Soul Exchange" targeting the set "Jinzo" for his "Deck Devastation Virus". This is NOT possible. As A does not control "Jinzo", he works as a monster without characteristics for A right now, even though he knows it is a "Jinzo".

WWe see: We can only tribute a set monster as a cost when we control the set card at this moment.

Contact Fusion: This special way of Summoning Fusion Monsters works without "Polymerisation". Contact Fusions can be conducted when all required monsters are on your side of the field. A contact fusion can be conducted even if all materials are in face-down Defense Position.

Example:

A can send a set "Gladiator Beast Bestiary" and a set "Gladiator Beast Laquari" back to his deck in order to Contact Fusion "Gladiator Beast Gyzarus".

Set monsters have NO effect.

Beispiele:

A has a set "Spirit Reaper" on his side of the field. B activates "Mind Control" targeting the set "Spirit Reaper".

• Because the set "Spirit Reaper" has no effect, he does not destroy himself although "Mind Control" targets him.
• B takes control of "Spirit Reaper". He can even Flip Summon him without "Spirit Reaper" destroying itself.

Exceptions are monsters that explicitly state in their effect text that they can be activated while set face-down:

A has a set "Big Shield Guardna" on his side of the field. B activates "Nobleman of Crossout" targeting "Big Shield Guardna".

• The effect of "Big Shield Guardna" negates the effect of "Nobleman of Crossout" because the Spell Card targeted this set Monster Card.

It is not possible to tribute a set monster for its own effect.

A has "The Creator" on his hand and a set "The Creator Incarnate" on his side of the field.

• A cannot activate "The Creator Incarnate" to summon "The Creator" from his hand. He needs to be flipped face-up first.

Some cards can only be activated in certain situations. These cards have activation requirements. They either can only be activated in a certain Phase or in reaction to an action (e.g. attack declaration).

Examples:

• "Mirror Force" - can only be activated in reaction to an opponent's attack declaration.
• "Torrential Tribute" - can only be activated in reaction to the Summon of a monster.
• "Drop Off" - can only be activated your opponent's Draw Phase when the action of drawing a card is conducted.

When cards with activation requirements get destroyed through the effect of another card (e.g. "Heavy Storm"), they cannot be chained because they do not fulfill their activation requirements.

Examples:

"Heavy Storm" destroys "Mirror Force".

• "Mirror Force" cannot be chained because the activation requirements are not met. It can only be activated in response to an attack.

A activates "Heavy Storm" to destroy his opponent's "Scapegoat", which the opponent chains. A also controls a set "Torrential Tribute".

• Because there are no monsters summoned, but only effects that will summon later on ("Scapegoat"), the activation of "Torrential Tribute" is not possible.
• The chain resolves, summoning first 4 Scapegoat Tokens, then destroying all Spell and Trap Cards.

Set Quick Spell Cards and Trap Cards that have no specific activation timing can be activated "anytime" (same for Quick Effects), provided that they have been set the previous turn. Of course, you still need priority to activate a card.



Beispiele:

• "Waboku", "Jar of Greed" and "Book of Moon" can be activated "anytime".

Even if a card would destroy a card that has no activation requirements, the card can be chained. Although the card is destroyed in the resolve, the effect activates! The reason lies in that an effect is no card. The only exceptions are permanent effects (Equip Spell Cards, Continous Spells and Traps), they need to be face-up on the field to have their effects. More about this in the chapter "chains".

This principle is used to check the legality of the activation of a card or an effect. It means that you can only activate a card or an effect when it is sure BEFORE the activation that the effect can fully resolve. If this is not the case, you cannot activate the card.

Generally, you assume that no more chain links are added to make the activation legal. These should have been activated earlier.

Examples:

• A cannot activate "Lightning Vortex" if there are no monsters on B's side of the field.
• "Hand Destruction" cannot be activated if one of the players has less than 2 cards in his hand.

The exceptions to the "Kara Uchi Principle" are Flip Effects:

Player A has a set "Morphing Jar" while B has only 4 cards left in his deck.

• A may activate "Morphing Jar" although it is obvious that the effect cannot fully resolve.
• Flip summons do not count as effect activations, they are actions.
• The effect will try to resolve as far as possible. Player B loses the game as he cannot draw all 5 cards.

Generally, card effects resolve where they are activated. Meaning: Player A activates a Spell Card on his side of the field. The effect of the card resolves on his side of the field, A gets the effect.

Advanced Example:

A controls a face-up "Remove Brainwashing" and has a "Destiny Hero - Disc Commander" in his graveyard. B activates "Monster Reborn" targeting "Disk Commander".

• "Destiny Hero - Disc Commander" is summoned to player B's side of the field.
• Before the effect of "Destiny Hero - Disc Commander" triggers, the permanent effects on the field are counted in. In this case, "Remove Brainwashing" causes "Destiny Hero - Disc Commander" to change to A's side of the field.
• Now "Destiny Hero - Disc Commander" triggers to his summon.

Although it is B summoning the Monster, it is A getting the effect. This is because the monster determines the controller of the effect upon activation of the effect.

Regarding activation costs, we sometimes have graveyard effects and field effects that do not seem to be such. Effects with activation costs always activate where the costs are paid.

Examples:

Player A has a face-up "Shadow-Imprisoning Mirror". B discards "D.D. Crow" as activation cost from his hand, targeting his opponent's "Treeborn Frog".

• Because "Shadow Imprisoning Mirror" only negates effects that activate on the field or in the graveyard, it cannot negate "D.D. Crow".
• "D.D. Crow" was discarded from the hand as a cost to activate its effect. The effect activates and resolves also on the hand, regardless where the card physically is.

"Destiny Hero - Malicious" is in B's graveyard. A controls "Shadow-Imprisoning Mirror". "Destiny Hero - Malicious" is banished from the graveyard as a cost to activate its effect.

• The costs were brought in the graveyard. Therefore, "Destiny Hero Malicious" activates in the graveyard.
• The permanent effect of "Shadow-Imprisoning Mirror" negates "Malicious".

An Infinite Loop is an effect combination in which several effects influence the game at the same time, causing a chain or a repetition of permanent effects that have no finite end. Infinite loops are forbidden.

If a player knows that the activation of a card causes an Infinite Loop, he CANNOT play this card or change the position of a card respective. If he does anyhow, this counts as misactivation, the card returns to its original position.

Example:

A controls a "Cyper Phoenix" in face-up Attack Position, an "Archfiend" monster and a "Falling Down". B only controls "Jinzo". A wants to take control over "Jinzo" with "Falling down".

• A cannot activate "Falling Down" because this would result in an Infinite Loop. "Jinzo" would just change control again and again.
• He has the possibility to change "Cyber Phoenix" into Defense Position so that his effect is no longer active. After this, he can activate "Falling Down".
• If he does so, he cannot change "Cyber Phoenix" into Attack Position as long as this would cause an Infinite Loop.

There exist situations where no player takes the fault in creating an Infinite Loop. If it comes to an Infinite Loop by accident, the card NEGATING something gets destroyed. Important for this mechanic is, that before activation it was not sure that this would lead into an Infinite Loop.

Example:

A played "Falling Down" on his opponent's "Jinzo". In addition, A has a set "Cyber Phoenix" on his side of the field. B plays a "Book of Taiyou" on "Cyber Phoenix".

• Because B did not know upon activation that he would cause an Infinite Loop, he can activate "Book of Taiyou".
• "Cyber Phoenix" is flipped into face-up Attack Position.
• Now, the Infinite Loop would begin, but this is forbidden. Still "Book of Taiyou" was a legal activation, so it cannot be taken back.
• In this case, the card NEGATING something is destroyed. "Cyber Phoenix" is therefore destroyed because he would negate "Falling Down" again and again.

There also exist legal loops. In these, the player causing the loop just names a number of times he wants to repeat something ("infinite" is no number). After it, he has to do another action.
Legal Loops can always be stopped manually. Because of this, they are not forbidden. As long as there exists a chance to stop the loop, it is perfectly legal.

Example:

A controls an "Ultimate Tyranno" in Attack Position. B has a set "Spear Cretin" and another one in the graveyard. A has no cards in his graveyard. A attacks the "Spear Cretin".

• Because both monsters have a mandatory effect and "Spear Cretin" cannot summon a monster from A's graveyard, this would normally lead into an Infinite Loop.
• But there is the possibility to summon "Spear Cretin" in face-up Attack Position. This means player B has to say how often he wants to summon "Spear Cretin" in set Defense position. After this, he has to choose another option.
• So in the end, player B has to summon "Spear Cretin" in face-up Attack Position, even if the loss in Life Points would cause him to loose the game.