* These ==OCG Rulings==[Regarding the effect "''You must have this many "Crystal Beast" cards in your Spell & Trap Zone to activate and to resolve these effects are cumulative. For example, if you have ''"]<ref name="No.7079">{{cite web|url=https://www.db.yugioh-card.com/yugiohdb/faq_search.action?ope=4 or more &cid=7079&request_locale=ja |title=Ancient City - Rainbow Ruins |website=Konami OCG Card Database |access-date=2023-02-25}}</ref>* It is not treated as an effect.[Regarding the effect "''● 1+''"]<ref name="No.7079"/>* It does not start a [[Chain Link]] and is applied in the Field Zone.[Regarding the effect "''● 2+''"]<ref name="No.7079"/>* It does not start a Chain Link and is applied in the Field Zone.* It can be applied during [[Crystal Beasts|Crystal Beastdamage calculation]]when you would take battle damage.[Regarding the effect "''● 3+''"]<ref name=" monsters No.7079"/>* It starts a Chain Link and can be activated in the Field Zone.* It can be activated directly in your [[Chain]] to the activation of a Spell & /Trap Card Zones. (It is a [[Spell Speed 2]], this card gets all of these effects except effect.)* It cannot be activated during the [[Damage Step]].[Regarding the effect "''● 4+''"]<ref name="No.7079"/>* It starts a Chain Link and can be activated in the Field Zone.* It can be activated during your Main Phase.[Regarding the effect "''● 5''"]<ref name="No.7079"/>* It starts a Chain Link and can be activated in the last oneField Zone.* It can be activated during your Main Phase.

* Only ===Q&A Rulings==={{Ruling| Q = When resolving the effect "''● 3+''" of "[[Ancient City - Rainbow Ruins]]", if I have 2 or less "[[Crystal Beast]]" cards in my Spell & Trap Zone, how does the effect resolve?| A = Even in that case, the activated effect "''● 3+''" resolves as usual. Similarly, when resolving the effect "''● 4+''" or "''● 5''", even if you no longer meet its conditions ("[[controllerAncient City - Rainbow Ruins]] of this card can use these effects" no longer has the gained effect), the effect resolves as usual.| cite = 6642| date = 2023-02-25}}

* If this card{{Ruling| Q = While the effect "'s first '● 1+''" of "[[Ancient City - Rainbow Ruins]]" is being applied, if an effectthat destroys multiple Spell/Trap Cards is activated, such as "This card cannot be [[destroyHeavy Storm]]ed by a card effect." is active, this card can be "[[targetDemise, King of Armageddon]]ed by ", or "[[Mystical Space TyphoonMalevolent Catastrophe]]", etc.the "[[Crystal Beast]]" cards in the Spell & Trap Zone are destroyed, but this card will is the "[[Ancient City - Rainbow Ruins]]" in the Field Zone also destroyed?| A = While the effect "''● 1+''" of "[[Ancient City - Rainbow Ruins]]" is being applied, "[[Ancient City - Rainbow Ruins]]" is not be destroyed when the effect of "[[destroyHeavy Storm]]ed" or "[[Demise, King of Armageddon]]" resolves.| cite = 6641| date = 2017-03-24}}

==Previously Official Rulings=={{Previously Official Rulings |UDE's Rulings =* If These effects are cumulative. For example, if you [[control]] this card and have at least 1 4 or more "[[Crystal Beasts|Crystal Beast]]" monsters in your [[Spell & Trap Card ZonesZone]], and they would this card gets all be [[destroy]]ed at of these effects except the same time then "[[Ancient City - Rainbow Ruins]]" is not [[destroy]]edlast one.

* This card’s effects are not applied until its activation is resolved. If you have 1 "[[Crystal Beast]]" monster in your Only the [[Spell & Trap Card Zones]] when you [[activatecontroller]] of this card, and your opponent Chains "[[Mystical Space Typhoon]]", etc., this card will be [[destroy]]edcan use these effects.

* This If this card’s first effect, “This card will cannot be [[destroy]]ed if your opponent plays by a card effect.” is active, this card can be [[Field Spell Cards|Field Spell Cardtarget]]ed by “[[Mystical Space Typhoon]], even if the effect "This ” etc., but this card cannot will not be destroyed by a card effect." is active[[destroy]]ed.

* If "you [[control]] this card and have at least 1 “[[Crystal Beasts|Crystal Beast]]" monsters ” in your [[Spell & Trap Card Zones]] are , and they would all be [[destroy]]ed in a [[Chain]] to at the activation of any of this card's effects that can be same time then “[[chainAncient City - Rainbow Ruins|Ancient City – Rainbow Ruins]]ed to, then this card's effect ” is not applied. The correct number of "[[Crystal Beasts|Crystal Beastdestroy]]" monsters must be in your [[Spell & Trap Card Zones]] when the effect [[resolve]]sed.

* This card's effect card’s effects are not applied until its activation is resolved. If you have 1 "Once per turn, you can halve the [[Battle DamageCrystal Beast]] you take." does not start a monster in your [[ChainSpell & Trap Card Zones]]. You choose whether or not to when you [[activate it during ]] this card, and your opponent Chains “[[Damage CalculationMystical Space Typhoon]], when you would take ” etc., this card will be [[Battle Damagedestroy]]ed.

* This card's effect "You can send 1 "If “[[Crystal Beasts|Crystal Beast]]" monster you [[control]] to the [[Graveyard]] to ” monsters in your [[negate]] the activation of a Spell or & Trap Card and [[destroyZones]] it." is are [[activatedestroy]]d ed in a [[Chain]] to a Spell or Trap Card. It is treated as the activation of any of this card’s effects that can be [[Spell Speed 2chain]]ed to, so you cannot [[Chain]] then this card’s effect to a [[Counter Trap Cards|Counter Trap Card]]is not applied. You can [[activate]] it multiple times in the same [[Chain]]. Sending a "The correct number of “[[Crystal Beasts|Crystal Beast]]" monster you ” monsters must be in your [[controlSpell & Trap Card Zones]] to when the effect [[Graveyardresolve]] is a [[costs|cost]] to [[activate]] this effects.

* This card's card’s effect "Once “Once per turn, during your you can halve the [[Main PhaseBattle Damage]], you can draw 1 cardtake." starts ” does not start a [[Chain]]. It can only be used once a turn, even if the number of "You choose whether or not to activate it during [[Crystal Beasts|Crystal BeastDamage Calculation]]" cards in your , when you would take [[Spell & Trap Card ZonesBattle Damage]] becomes less than 4, and then becomes 4 or more again after you have used it in a given turn.

* This card's card’s effect “You can send 1 "Once per turn, during your [[Main PhaseCrystal Beast]], " monster you can [[Special Summoncontrol]] 1 "to the [[Crystal Beasts|Crystal BeastGraveyard]]" card from your to [[negate]] the activation of a Spell & or Trap Card Zones|and [[destroy]] it.” is [[activate]]d in a [[Chain]] to a Spell & or Trap Card Zone. It is treated as [[Spell Speed 2]], so you cannot [[Chain]]" starts this effect to a [[ChainCounter Trap Card|Counter-Trap Card]]. It You can [[targetactivate]]s 1 "it multiple times in the same [[Chain]]. Sending a “[[Crystal Beasts|Crystal Beast]]" card in your ” monster you [[control]] to the [[Graveyard]] is a [[cost]] to [[Spell & Trap Card Zonesactivate]]this effect.

==UDE FAQ==* The third This card’s effect of negating Spell and Trap Cards cannot “Once per turn, during your [[Main Phase]], you can draw 1 card.” starts a [[Chain]]. It can only be activated in used once a turn, even if the number of “[[Damage StepCrystal Beast]].^{<font class=plainlinks>” cards in your [[http://entertainmentSpell & Trap Card Zones]] becomes less than 4, and then becomes 4 or more again after you have used it in a given turn.upperdeck.com/community/forums/thread/843927.aspx source]</font>}

==Mentions in Other Rulings==* '''This card’s effect “Once per turn, during your [[Card Rulings:Light and Darkness Dragon|Light and Darkness DragonMain Phase]]''': “, you can [[Light and Darkness DragonSpecial Summon]]” cannot 1 "[[negateCrystal Beast]] the activation of the " card from your [[Ignition Monster Effects|Ignition]]-like effect of [[Continuous Spell Cards& Trap Card Zones|Continuous Spell]] or [[Continuous & Trap Cards|Trap CardsCard Zone]] (“” starts a [[Ultimate OfferingChain]]”, etc.) or It [[Field Spell Cardstarget]] (s 1 “[[Ancient City - Rainbow RuinsCrystal Beast]]”, etc.). “card in your [[Light and Darkness Dragon|Light and Darkness Dragon’s]]” second effect activates when a Spell or & Trap Card is first activated (placed face-up onto the field or flipped face-up)Zones]].

==OCG =Mentions in Other Rulings===* If cards like '''[[Heavy StormCard Rulings:Field Barrier|Field Barrier]] would destroy ''': This card only prevents the [[Crystal Beasts]] from your [[activation of Field Spell & Trap Card Zones|Cards themselves. The effects of a Field Spell & Trap Card Zonealready on the field (like “[[Ancient City - Rainbow Ruins]], ”) can still be activated while this card will not be [[destroy]]edis in play.

* '''[[Card Rulings:Last Resort|Last Resort]]''': This card will be is resolved as follows: First, select 1 “[[destroyAncient City - Rainbow Ruins]]ed if another [[” from your Deck and place it in your Field Spell Cards|Card Zone, then <s>your opponent’s Field Spell Card]] is [[activate]]d. This is because it is being destroyed by game mechanics, </s><ref group="Out of Date" name="Two Field Spell"/> and not a they draw one card effect.

* You cannot send '''[[Crystal BeastsCard Rulings:Last Resort|Last Resort]] in your ''': You can activate “[[Last Resort]]” while you have a Field Spell & Trap Card Zones|in your Field Spell & Trap Card Zone]] to the Graveyard to . When “[[activateLast Resort]] this effect” resolves, since the cards in the [[Field Spell & Trap Card Zones|in your Field Spell & Trap Card Zone]] are not treated as is <s>destroyed</s><ref group="monstersOut of Date">According to the [https://yugiohblog.konami.com/articles/?p=6351 new game mechanics for Field Spell Cards], but "if you activate a new Field Spell Card to replace another, then the old one is sent to the Graveyard, not destroyed.</ref> and “[[Continuous Spell CardsAncient City - Rainbow Ruins]]"” is placed into your Field Spell Card Zone.

* If '''[[Card Rulings:Light and Darkness Dragon|Light and Darkness Dragon]]''': “[[Light and Darkness Dragon]]” cannot [[negate]] the activation of the [[Ignition-like effect]] of [[Macro CosmosContinuous Spell Card|Continuous Spell]]or [[Continuous Trap Card|Trap Cards] ] ({{sic|{{Span|<nowiki>The effect of "Ultimate Offering" is on a Quick-like Effect</nowiki>|“Ultimate Offering”}}}}, etc.) or [[Field Spell Card]]s (“[[Ancient City - Rainbow Ruins]]”, etc.). “[[Light and Darkness Dragon|Light and Darkness Dragon’s]]” second effect activates when a Spell or Trap Card is first activated (placed face-up onto the field you cannot activate this card's third effector flipped face-up).

===Judge List Rulings===* You can The "''3+''" effect of this card cannot be activated during the [[activateDamage Step]] the effect(s) of "[.<ref>[http://web.archive.org/web/20071101060844/http:/entertainment.upperdeck.com/community/forums/thread/847126.aspx UDE Judge List]: Ancient City - – Rainbow Ruins]]" more than once in the same [[Chain]].effect three</ref>

* If you activate an effect that A card like "[[Magic Jammer]]" can only be activated once per turn, and chained to ''the initial activation'' of "[[Ancient City - Rainbow Ruins]]" is then removed from . If ''the field and effect'' of "[[Ancient City - Rainbow Ruins]]" is re-activatedthen "[[Magic Jammer]]", ect, you can activate the effect againcannot be chained.<ref>[http://web.archive.org/web/20071101063805/entertainment.upperdeck.com/community/forums/thread/850949.aspx UDE Judge List]: Ancient city vs negation</ref>

* The second If you have "[[Ancient City - Rainbow Ruins]]" face-up on the field and your opponent activates another [[Field Spell Card]] you can chain "[[Ancient City - Rainbow Ruins]]'s" third effect is activated in to negate the activation of the [[Damage StepField Spell Card]] <s>and "[[Ancient City - Rainbow Ruins]]" will not be destroyed by game mechanics</s>.<ref group="Out of Date" name="Two Field Spell"/><ref name="UDEJL-ACRR">[http://web.archive.org/web/20071013014541/entertainment.upperdeck.com/community/forums/thread/854302.aspx UDE Judge List]: Active Field Card versus Set Field Card ...</ref>

* The second effect does not use a Chain, so If you cannot use activate "[[Damage CondenserAncient City - Rainbow Ruins]]" to summon while you have a monster face-up "[[Crystal Beast]]" card in your [[Spell & Trap Card Zone]] and the opponent chains with "[[Mystical Space Typhoon]]", then halve the battle damage received"[[Ancient City - Rainbow Ruins]]" will be destroyed. You can halve the damage"[[Ancient City - Rainbow Ruins]]'s" first effect is not applied since "[[Ancient City - Rainbow Ruins]]" hasn't resolved yet, and then use so it does not protect "[[Ancient City - Rainbow Ruins]]" from "Damage Condenser[[Mystical Space Typhoon]]'s" to summon a monstereffect.<ref name="UDEJL-ACRR"/>

===Out of Date===* When This card will be [[destroy]]ed if your opponent plays a [[Field Spell Card]], even if the second effect “This card cannot be destroyed by a card effect.” is activated, fractional damage is rounded upactive.<ref group="Out of Date" name="Two Field Spell">According to the [https://yugiohblog.konami. If you would take 1225 damagecom/articles/?p=6351 new game mechanics for Field Spell Cards], but use this effectnow both players can have an active Field Spell Card on their field at the same time, then you would take 613 damage insteadso the other player's Field Spell Card will not be destroyed if their opponent plays one.</ref>}}

* The fifth effect uses a chain. You can use ==Notes=====Out of Date===<references group="[[Royal Oppression]]Out of Date" to negate it. (Of course, "Ancient City - Rainbow Ruins" will not be destroyed, so the effect can be activated again.)/>