union arena code geass booster box Arena: quality cards in the lineup use new visuals Union Arena - Code Geass

The only time the characteristics of the back face really matter is when the permanent is on the battlefield with its back face up

IIRC in Yugioh there is only a certain number of Blue-Eyes (from the show?), so you could put a rule on the card 'there may only be X Blue-Eyes on the battlefield at any time', Star Wars CCG used to have permanents that you could have 2 or 3 copies of in play, in addition to stuff you could only have 1 of, the concept would work fine here too, only this could care about both players' boards

Wizards could have gone a few different directions with the reskin, including using an actual Octopus legend like Marvo, Deep Operative

S9 Star Birth is out of print with no announced reprint

place it on the top of the Deck

GSE Gold Secret Dark Advance X TRAP During either player's Main Phase or Battle Phase: Target 1 monster in your Graveyard with 2400 or more ATK and 1000 DEF