Hello, I've been searching the web for rulings and examples on when "De-Fusion" can summon materials and when not. After a while I found these bits (not related to one another):

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If "Proto-Cyber Dragon" is used in the Fusion Summon of "Cyber Twin Dragon", and "De-Fusion" is used on that "Cyber Twin Dragon", you cannot Special Summon the "Proto-Cyber Dragon" from the Graveyard because its name is not 1 of the listed Fusion-Material Monsters. (It's no longer treated as "Cyber Dragon" while in the Graveyard.)
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There's no contradiction. The monster still has to be a valid Fusion Material monster to be Special Summoned. "Proto-Cyber Dragon" (without its effect) is not a valid Fusion Material monster for (e.g.) "Cyber Twin Dragon", so it cannot be Special Summoned. The effect of "King of the Swap" and friends is active even while the monster is in the Graveyard, so it is a valid Fusion Material monster for [whatever was Summoned]. Note that "Cyber Dragon Zwei" is still treated as "Cyber Dragon" while in the Graveyard, so it will be Special Summoned.
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I finally got a better understanding of how it works, except for a tiny detail......

Lets say I summon Chimeratech Fortress Dragon with: A Proto-Cyber Dragon (whoms name is treated as Cyber Dragon) plus two more (random) machine monsters. This is possible, correct? If not, please elaborate and ignore the rest.

Now what happens when I use De-Fusion on it? Based on everything I've read and the bits I've pasted above it SHOULD be possible to special summon the Proto-Cyber Dragon (and the other two machine monsters). Why? Well Proto-CD may no longer qualify as a listed material (in place of a Cyber Dragon) but it's still a machine monster (which is also listed).

Quick breakdown, which of the two scenarios is correct?

1. Do fusion as stated above.
2. Use De-Fusion.
3. Check if all used materials are still in graveyard. If not -> skip summoning of ALL used materials.
4. Check each material to see if it matches a(ny) listed material. If any fails -> skip summoning of ALL used materials.

-OR-

1. Do fusion as stated above.
2. Use De-Fusion.
3. Check if all used materials are still in graveyard. If not -> skip summoning of ALL used materials.
4. Check the combination of materials to see if they can still form the (original) fusion. If not -> skip...etc...


In short, the question I have is this: do the materials used for the fusion only have to be a match induvidually or do all of them together still need to fulfill the complete set of listed materials? Right now I only have the assumption and when you consider the history of confusion over these two cards I wanted the input of those more qualified than me. :)


Thank you for your time and sorry for the lengthy post. -_-

De-Fusion wouldn't be able to Special Summon anything if used on Chimeratech Fortress Dragon because it can only Special Summon Fusion Material Monsters used in the "Fusion Summon" of the Fusion Monster. Chimeratech Fortress Dragon is never "Fusion Summoned", but plainly Special Summoned.

But switch it with Chimeratech Over Dragon (same materials, but actually Fusion Summoned) and it would depend.

Did you actually use Proto-Cyber Dragon in place of "Cyber Dragon" for that Fusion Material Monster?

If so, then the name ruling will still apply and you could not Special Summon "Proto-Cyber Dragon" from your Graveyard and, consequently, none of the other Fusion Material Monsters as the Special Summoning of the Fusion Material Monsters used in the Fusion Summon from your Graveyard is all or nothing. (If you're unable to Special Summon even 1 of the Fusion Material Monsters, then you are unable to Special Summon anything.) It would not matter if you used Cyber Dragon itself or Cyber Dragon Zwei as (one of) the other Machine-Type monster(s) alongside it as De-Fusion would only check for which "Cyber Dragon" was actually used.

However, if you used Proto-Cyber Dragon as one of the other Machine-Type monsters, then you CAN Special Summon Proto-Cyber Dragon from your Graveyard as, in this case, name is not being cared about, but just the Type as a Machine-Type monster.