Why can't I summon Cyber End Dragon using Light Hex sealed fusion + Proto Cyber Dragons

I might have went stupid or something. But I am trying to figure out why the last scenario below does not let me sumon Cybe End Dragon using The Light Hex sealed fusion 2nd effect.

Cyber D Drei + Cyber D Zwei + Hex = Hex activates
Proto Cyber + Cyber D Drei + Hex = Hex activates
Proto Cyber + Proto Cyber + Hex = Hex can't activate (Why?)

Answer

Answer List

anoymous

Konami ruined the skill because of those people who used it for other decks.

anoymous

Lol, I meant anon below. Oh well.
Also to the question of the second situation. If the Proto Cyber is summoned using the Skill, it won't work.
But since Proto is also available as a regular card, summoning a regular Proto WILL allow Hex to work.

anoymous

The anon above is Correct. Combining the skill "Cyber Style" with Hex does NOT work.
Cyber Style only allows the Proto Cybers to be used for a fusion summon. But the Hex Sealed Fusion card effects are NOT Fusion Summons. They're Special Summons.
Hence also why fusions summoned by Hex cannot be revived. It's not a "corect" fusion summoning.

anoymous

I'm guessing for the 3rd situation, you used Cyber Style skill. The proto generated from the skill cannot be tribute or used as material except for fusion summon.
Hex sealed effect is special summon (not fusion)

But strange thing is for the 2nd situation. Unless of course if that proto is the one you played from your actual card, then this should justify everything.