Effect
(This card is also always treated as "Legendary Dragon Timaeus".) Target 1 "Dark Magician" monster you control; Fusion Summon 1 Fusion Monster from your Extra Deck that mentions that monster on the field as material, using it as the Fusion Material. You can only activate 1 "The Eye of Timaeus" per turn.
This is not a card that mentions "Dark Magician" in its card name.
【Regarding "This card's name is also treated as 'The Eye of Timaeus' while on the field/in the GY"】
This is not treated as an effect.
【Regarding the ① effect】
At the time of resolution, you perform the action of "using only that 1 monster as Fusion Material." Afterward, you perform the action of "Fusion Summoning 1 Fusion Monster that lists that card's name as Fusion Material."
"A Fusion Monster that lists that card's name as Fusion Material" refers to a Fusion Monster whose text lists the card name of the monster sent to the Graveyard as a Fusion Material.
The action of using the Fusion Material and the action of Special Summoning do not occur simultaneously.
Unless another effect is being applied, the Fusion Material monster is sent to the Graveyard; however, due to the application of other effects, the Fusion Material may be sent somewhere other than the Graveyard. Even in that case, if the Fusion Material monster has left the hand or field, the Fusion Monster is still Special Summoned.
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