The Light Hex Sealed Fusion and King of The Swamp?

Question

Will I be able to use either of these cards in a Cyber Dragon deck?

Some people say you can't use either of these cards for a subsitute for a Cyber Dragon. Is this true?

Answer 1

I believe it is true because both fusions state that they can only be fusion summoned using the above fusion material monsters which means you can only use Cyber Dragons and nothing else.

Answer 2

no u cant use none ur allowed to use cyber dragon/

proto cyber dragon not any other cards.

Answer 3

I have the game yugioh world championship 2007 and there I can use The Light Hex Sealed Fusion but not king of the swamp