Card Rulings:Ancient City - Rainbow Ruins

• These effects are cumulative. For example, if you have 4 or more "Crystal Beast" monsters in your Spell & Trap Card Zones, this card gets all of these effects except the last one.

• Only the controller of this card can use these effects.

• If this card's first effect, "This card cannot be destroyed by a card effect." is active, this card can be targeted by "Mystical Space Typhoon", etc., but this card will not be destroyed.

• If you control this card and have at least 1 "Crystal Beast" in your Spell & Trap Card Zones, and they would all be destroyed at the same time then "Ancient City - Rainbow Ruins" is not destroyed.

• This card’s effects are not applied until its activation is resolved. If you have 1 "Crystal Beast" monster in your Spell & Trap Card Zones when you activate this card, and your opponent Chains "Mystical Space Typhoon", etc., this card will be destroyed.

• This card will be destroyed if your opponent plays a Field Spell Card, even if the effect "This card cannot be destroyed by a card effect." is active.

• If "Crystal Beast" monsters in your Spell & Trap Card Zones are destroyed in a Chain to the activation of any of this card's effects that can be chained to, then this card's effect is not applied. The correct number of "Crystal Beast" monsters must be in your Spell & Trap Card Zones when the effect resolves.

• This card's effect "Once per turn, you can halve the Battle Damage you take." does not start a Chain. You choose whether or not to activate it during Damage Calculation, when you would take Battle Damage.

• This card's effect "You can send 1 "Crystal Beast" monster you control to the Graveyard to negate the activation of a Spell or Trap Card and destroy it." is activated in a Chain to a Spell or Trap Card. It is treated as Spell Speed 2, so you cannot Chain this effect to a Counter Trap Card. You can activate it multiple times in the same Chain. Sending a "Crystal Beast" monster you control to the Graveyard is a cost to activate this effect.

• This card's effect "Once per turn, during your Main Phase, you can draw 1 card." starts a Chain. It can only be used once a turn, even if the number of "Crystal Beast" cards in your Spell & Trap Card Zones becomes less than 4, and then becomes 4 or more again after you have used it in a given turn.

• This card's effect "Once per turn, during your Main Phase, you can Special Summon 1 "Crystal Beast" card from your Spell & Trap Card Zone" starts a Chain. It targets 1 "Crystal Beast" card in your Spell & Trap Card Zones.

Japanese Rulings

• If cards like Heavy Storm would destroy the Crystal Beasts from your Spell & Trap Card Zone, this card will not be destroyed.

• This card will be destroyed if another Field Spell Card is activated.

• You cannot send Crystal Beasts in your Spell & Trap Card Zone to the Graveyard to activate this effect, since the cards in the Spell & Trap Card Zone are not treated as "monsters", but "Continuous Spell Cards".

• If Macro Cosmos is on the field you cannot activate this card's third effect.

• You can activate Ancient City - Rainbow Ruins more than once in the same Chain.