Iron Core of Koa'ki Meiru

 This card appears in the artwork of Iron Core Immediate Disposal, Reckoned Power, and Iron Core Luster.

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The English name, Koa'ki Meiru, is supposedly named after the Japanese pronunciation of Core Chimera.

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The symbol on the device in the card image appears on all of the Koa'ki Meiru Monsters' body and/or weapon.

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This is considered to be the most important card in a Koa'ki Meiru Deck, since most Koa'ki Meiru Monsters and Koa'ki Meiru support cards revolve around the use of this card.

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Based on the number of Rock-Type Koa'ki Meiru monsters compared to others, one can assume the Iron Core is most compatible with Rock Monsters.

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TCG Rulings

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Both effects of “Iron Core of Koa’ki Meiru” start a chain. Sending a “Koa’ki Meiru” monster to the Graveyard is a cost to activate the second effect.: Raging Battle -- Card Rulings (version 1.2)

While “Macro Cosmos” is active, you cannot send “Iron Core of Koa’ki Meiru” to the Graveyard to pay the cost of keeping your “Koa’ki Meiru” monster on the field. So you must either pay the reveal cost, or destroy the monster.

Mentions in Other Rulings

Core Compression: Revealing “Iron Core of Koa’ki Meiru” and discarding 1 “Koa’ki Meiru” monster are both costs.

Iron Core Immediate Disposal: You cannot activate “Iron Core Immediate Disposal” unless there is an “Iron Core of Koa’ki Meiru” in your Deck.

Iron Core Luster: Revealing "Iron Core of Koa'ki Meiru" is a cost.

Iron Core Specimen Lab: Revealing "Iron Core of Koa'ki Meiru" is a maintenance cost to keep this card on the field.

Koa'ki Meiru Hydro Barrier: Returning “Iron Core of Koa’ki Meiru” from your hand to the top of the Deck is a cost.

Koa'ki Meiru Sandman: Discarding "Iron Core of Koa'ki Meiru" or revealing a Rock-Type monster is a cost, not an effect.

Koa'ki Meiru Sea Panther: Sending 1 "Iron Core of Koa'ki Meiru" from your hand to the Graveyard is a cost.

Koa'ki Meiru Shield: If there are less than 2 "Iron Core of Koa'ki Meiru" in your Graveyard when "Koa'ki Meiru Shield" resolves, the effect to destroy your opponent's monsters will still apply.

Koa'ki Meiru Speeder: Revealing “Iron Core of Koa’ki Meiru” is a cost to activate this effect.

Koa'ki Meiru Speeder: You can activate this effect once for each “Iron Core of Koa’ki Meiru” you draw during the Draw Phase.

Koa'ki Meiru Speeder: If you control multiple copies of “Koa’ki Meiru Speeder” and you draw “Iron Core of Koa’ki Meiru” during your Draw Phase, you can activate the effect of both monsters in a Chain.

"Koa'ki Meiru Urnight": Revealing “Iron Core of Koa’ki Meiru” is a cost to activate the effect.

"Koa'ki Meiru Tornado“Iron Core of Koka’ki Meiru” from your hand to the top of the Deck is a cost.

Nega-Ton Corepanel: If you don't control a face-up "Koa'ki Meiru" monster or don't have "Iron Core of Koa'ki Meiru" in your Graveyard when this card resolves, its effect is still applied.

Reckoned Power: Revealing “Iron Core of Koa’ki Meiru” is a cost to activate this card.

Urgent Synthesis: Returning 1 “Iron Core of Koa’ki Meiru” to the Deck is a cost to activate “Urgent Synthesis.” The effect does not target.

Urgent Synthesis: You cannot activate “Urgent Synthesis” while “Transmigration Break” is active, as you cannot pay the cost to return “Iron Core of Koa’ki Meiru” to the Deck.

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OCG Rulings

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Both of this card's effects which add it from your Graveyard to your hand start Chains.: Spell Card > Iron Core of Koa'ki Meiru

Sending a "Koa'ki Meiru" monster from your hand to the Graveyard is a cost to activate the effect which adds this card from your Graveyard to your hand.

If you activate the effect of "Iron Core of Koa'ki Meiru" instead of drawing and your opponent chains "Disappear"/"D.D. Crow"/etc to remove from play "Iron Core of Koa'ki Meiru", then "Iron Core of Koa'ki Meiru" will not be returned to the hand and you will not draw. This is because you activated the effect of "Iron Core of Koa'ki Meiru" instead of drawing.: When "Iron Core of Koa'ki Meiru" is removed from play when resolving its effect, it is not added to the hand, but after that can you draw?

If you have zero cards in your Deck, then during your Draw Phase you cannot draw, so you cannot activate the effect of "Iron Core of Koa'ki Meiru". You cannot draw, so you will lose the Duel.: When you cannot draw because there are zero cards in your Deck, can you instead add a "Iron Core of Koa'ki Meiru" to your hand?

While "Iron Core of Koa'ki Meiru" is in your Graveyard during the Draw Phase, both the effect of adding it to you hand instead of drawing and the effect of adding it to your hand by sending a "Koa'ki Meiru" monster to the Graveyard both start Chains.: Do the effects which adds a "Iron Core of Koa'ki Meiru" from the Graveyard to the hand start Chains?

During the Draw Phase, if you have multiple copies of "Iron Core of Koa'ki Meiru" in your Graveyard, then you can activates the effects of all copies instead of drawing. However, only the effect of the copy placed highest on the Chain will resolve and all other copies will resolve without effect, because you already added a card to your hand instead of drawing. In total, you will only add one copy of "Iron Core of Koa'ki Meiru" to your hand.: When you have multiple copies of "Iron Core of Koa'ki Meiru" in your Graveyard, can all copies be added to the hand instead of drawing?

If you activate an effect like that of "Iron Core of Koa'ki Meiru" or "Magical Blast" or "Spirit Burner" instead of drawing, then if an effect like that of "D.D. Crow" or "Disappear" is chained so that "Iron Core of Koa'ki Meiru" is no longer in the Graveyard when resolving its effect, then you do not add "Iron Core of Koa'ki Meiru" to your hand. However, you still cannot draw, since you already chose to activate the effect of "Iron Core of Koa'ki Meiru" instead of draw.: If "Iron Core of Koa'ki Meiru" is removed from play when resolving its effect, then you cannot add it to your hand, but afterwards can you still perform your normal draw?

Suppose that the effect of "Prohibition" has declared "Iron Core of Koa'ki Meiru", and afterwards "Iron Core of Koa'ki Meiru" is Summoned to the field by the effect of "Magical Hats". "Iron Core of Koa'ki Meiru" has already been declared for "Prohibition", so "Iron Core of Koa'ki Meiru" cannot be "played". Thus, you cannot activate its effects after it is sent to the Graveyard.: If "Iron Core of Koa'ki Meiru" is declared for "Prohibition", then are you unable to activate its effects which add it to your hand from your Graveyard?

Mentions in Other Rulings

Automatic Laser: You cannot activate "Automatic Laser" if the "Iron Core of Koa'ki Meiru" in your hand is already revealed by the effect of "Ceremonial Bell" or "Respect Play".: Can "Automatic Laser" be activated if "Iron Core of Koa'ki Meiru" is already revealed?

Core Compression: Revealing one "Iron Core of Koa'ki Meiru" from your hand and discarding one "Koa'ki Meiru" monster is a cost to active "Core Compression".: Spell Card > Core Compression

Core Overclock: Discarding one "Iron Core of Koa'ki Meiru" is an activation cost for the ATK-increasing effect.: Spell Card > Core Overclock

Iron Core Immediate Disposal: You cannot activate "Iron Core Immediate Disposal" when you have no copy of "Iron Core of Koa'ki Meiru" in your Deck.: Spell Card > Iron Core Immediate Disposal

Iron Core Luster: Revealing one "Iron Core of Koa'ki Meiru" is a cost to activate "Iron Core Luster".: Trap Card > Iron Core Luster

Iron Core Luster: You cannot activate "Iron Core Luster" while "Iron Core of Koa'ki Meiru" is already revealed, such as by "Respect Play" or "Ceremonial Bell".: Can "Iron Core Luster" be activated while "Iron Core of Koa'ki Meiru" is already revealed?

Iron Core Specimen Lab: The text "During each of your End Phases, destroy this card unless you reveal 1 Iron Core of Koa'ki Meiru in your hand." of "Iron Core Specimen Lab" is a maintenance cost.: Spell Card > Iron Core Specimen Lab

Koa'ki Meiru Hydro Barrier: Returning an "Iron Core of Koa'ki Meiru" from your hand to the top of your Deck is a cost to activate the effect of "Koa'ki Meiru Hydro Barrier".: Effect Monster > Koa'ki Meiru Hydro Barrier

Koa'ki Meiru: The text "During each of your End Phases, destroy this card unless you send 1 "Iron Core of Koa'ki Meiru" from your hand to the Graveyard ." of "Koa'ki Meiru" monsters is a Maintenance Cost.: Effect Monster > Koa'ki Meiru Ice: Effect Monster > Koa'ki Meiru Drago: Effect Monster > Koa'ki Meiru Guardian: Effect Monster > Koa'ki Meiru Powerhand: Effect Monster > Koa'ki Meiru Valafar: Effect Monster > Koa'ki Meiru Speeder: Koa'ki Meiru Crusader: Effect Monster > Koa'ki Meiru Rooklord: Effect Monster > Koa'ki Meiru Sea Panther: Effect Monster > Koa'ki Meiru Urnight: Effect Monster > Koa'ki Meiru Sandman

Koa'ki Meiru: While your hand is revealed by the effect of "Respect Play"/"Ceremonial Bell"/etc, you cannot perform "reveal 1 Normal Trap Card from your hand." as a Maintenance Cost for "Koa'ki Meiru Powerhand". You must either perform either "send 1 "Iron Core of Koa'ki Meiru" to the Graveyard" or "destroy this card".: Can a Trap Card in the hand be shown as a Maintenance Cost for "Koa'ki Meiru Powerhand" while the hand is revealed by the effect of "Respect Play"?

Koa'ki Meiru: While "Macro Cosmos" is activate, you cannot perform "send 1 "Iron Core of Koa'ki Meiru" to the Graveyard" as a Maintenance Cost for "Koa'ki Meiru Doom". You must either perform either "reveal 1 Fiend-Type monster from your hand." or "destroy this card".: While "Macro Cosmos" is active, can a "Iron Core of Koa'ki Meiru" be sent to the Graveyard as a Maintenance Cost for "Koa'ki Meiru Doom"?

Koa'ki Meiru: The text "During each of your End Phase, destroy this card unless you send 1 "Iron Core of Koa'ki Meiru" from your hand to the Graveyard." of "Koa'ki Meiru Valafar" is a Maintenance Cost. It cannot be negated by the effect of "Skill Drain", so you must still pay the Maintenance CostStandby Phases.: Can the effect of "Skill Drain" negate the Maintenance Cost of "Koa'ki Meiru Valafar" etc?

Koa'ki Meiru Sea Panther: Sending one "Iron Core of Koa'ki Meiru" to the Graveyard is a cost to activate the effect of "Koa'ki Meiru Sea Panther" which returns a Spell Card to the top of your Deck. This is an Ignition Effect which targets one Spell Card in your Graveyard.

Koa'ki Meiru Speeder: When you draw "Iron Core of Koa'ki Meiru", the effect of "Koa'ki Meiru Speeder" is an optional Trigger Effect. Showing to your opponent the "Iron Core of Koa'ki Meiru" you just drew is a cost to activate this effect.

Koa'ki Meiru Speeder: When you draw multiple copies of "Iron Core of Koa'ki Meiru" simultaneously, if you activate the effect of "Koa'ki Meiru Speeder", then you only show one copy of "Iron Core of Koa'ki Meiru" to your opponent.: When you activate the effect of "Koa'ki Meiru Speeder" when you draw multiple copies of "Iron Core of Koa'ki Meiru", do you show all copies to your opponent?

Koa'ki Meiru Speeder: When you draw an "Iron Core of Koa'ki Meiru" as your normal draw, if you wish to activate the effect of "Koa'ki Meiru Speeder", then you must activate it when the "Iron Core of Koa'ki Meiru" is drawn. (You cannot activate the effect at a later time.): When can you activate the effect of "Koa'ki Meiru Speeder"?

Koa'ki Meiru Speeder: If you draw "Iron Core of Koa'ki Meiru" in the middle of resolving a Chain, then you miss the timing and cannot activate the effect of "Koa'ki Meiru Speeder.

Koa'ki Meiru Tornado: Returning an "Iron Core of Koa'ki Meiru" from your hand to the top of your Deck is a cost to activate the effect of "Koa'ki Meiru Tornado".: Effect Monster > Koa'ki Meiru Tornado

Koa'ki Meiru Urnight: Revealing one "Iron Core of Koa'ki Meiru" to the opponent is a cost to activate the effect of "Koa'ki Meiru Urnight" which Special Summons a Level 4 or lower "Koa'ki Meiru" monster from your Deck.

Reckoned Power: Revealing one "Iron Core of Koa'ki Meiru" is a cost to activate "Reckoned Power".: Trap Card > Reckoned Power

Urgent Synthesis: Returning one "Iron Core of Koa'ki Meiru" from your Graveyard to your Deck is a cost to activate "Urgent Synthesis".: Spell Card > Urgent Synthesis