Inspired by vantage ( Doma arc recreation for this meta)

Dark Magician Girl the Dragon Knight
DARK/Dragon/Fusion/8/2600/1700
This card can only bee Special Summoned from the Extra Deck and cannot be Special Summoned by other ways..This card can only be summoned by banishing 1 Spellcaster-Type monster and 1 Dragon-Type monster from your hand,or your side of the field(This Special Summon is treated as a fusion summon). If this card attacks or is attacked: Send one card from your hand to the graveyard; destroy that monster before the Damage Step.

Amulet Dragon
Dark/Dragon/Fusion/8/2900/1700
This card can only bee Special Summoned from the Extra Deck and cannot be Special Summoned by other ways..This card can only be Special summoned by banishing 1 Spellcaster-Typer monster and 1 Dragon-Type monster monster from your hand, or on your side of the field This Special Summon is treated as a fusion summon).This card gains 300 ATK for each Spell Card in your Graveyard.


Doom Virus Dragon
Dark/Dragon/Fusion/5/1900/2000
This card can only bee Special Summoned from the Extra Deck and cannot be Special Summoned by other ways..This card can only be Special Summoned by banishing 1 Dragon-Type monster monster, and 1 "Virus" card from your hand, or on your side of the field from play (This Special Summon is treated as a fusion summon). This card gains the effect of "Virus" card used to Fusion Summon it.

Mirror Force Dragon
Light/Dragon/Fusion/Effect/8/2800/2000
This card can only bee Special Summoned from the Extra Deck and cannot be Special Summoned by other ways. This card can only be Special Summoned by banishing 1 Dragon-Type monster and 1 Miror Force from your hand or on your side of the field from play. When this card battles with an opponent's monster with equal or more ATK, destroy all face-up monsters your opponent controls at the start of the Damage Step, and inflict damage to your opponent equal to the total difference in ATK between this card and each of the destroyed monsters with lower ATK than this card.

Guardian Dreadscythe
Earth/Zombie/Effect/2500/2000
This card cannot be Normal Summoned or Set. This card can only be Special Summoned from your hand or Deck in Defense Position when "Guardian Eatos" is removed from the field by an Opponent's card effect. This card gains 500 ATK
for each monster in your Graveyard. If this card would be destroyed (either by battle or by card effect), you must discard 1 card instead.

Guardian Treasure
Spell:Continuous
Banish 5 cards from your hand, then draw 2 cards. As long as this card remains face up on the Field, you can draw 1 more card in addition to your normal draw. Destroy this card during your 3nd Standby Phase after activation.

Card of Demise
Spell:Normal
Banish all cards on your side of the field. Draw cards until you have 5 cards in your hand. During your 2nd Standby Phase after activation this card, send all cards in your hand and on the field,to the Graveyard. You cannot Special Summon a monster(s), or conduct your Battle Phase during the turn you activate this card.

Blue Flame Swordsman
This card can be Special Summoned from your Deck, or Hand when "Flame Swordsman" is removed from the field. During either player's turn, you can have this card lose ATK (Max 500) to have another face-up monster gain an equal amount of ATK. When this card is destroyed and sent to the Graveyard, Special Summon 1 "Flame Swordsman" from your Graveyard or your Extra Deck.

Junk Dealer
Discard 1 card form your hand. Select up to 2 Machine-type monsters in your Graveyard. Special Summon them in Attack Position and halve their original ATK.Monster's Special Summoned by this card effect have their effects negated, and cannot be used as Synchro Material Monster, or be tributed.

What about the Legendary Dragons?

The Eye of Timaeus
LIGHT, Level 10, Dragon/Effect
ATK/0, DEF/0
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Cannot be played face-down. The Normal Summon of this card is treated as a Special Summon. This card cannot be Summoned any other way. The summon/activation and effects of this card cannot be negated or responded to. Destroy this card if you control "The Seal of Orichalcos". The Original ATK and DEF of this card is equal to the ATK/DEF (whatever Position it's in) of the monster it battles with. When this card is summoned: you can send it to the Graveyard with 1 other monster you control, and Fusion Summon a Fusion monster from your Extra Deck that lists this card and that 1 monster as Fusion Materials.

Hermos and Critias would be the same. Hermos' equip spells would list the Materials and include the text "This card is stored in the Extra Deck and is also treated as a Fusion monster. This card cannot be summoned except by "Claw of Hermos". When this card is Fusion Summoned, it is equipped to 1 monster you control."