Any card that lets you give control of that permanent to an opponent or force them to make a copy of it puts them under an alternate loss condition, which is a roundabout way to win the game
But in terms of what digital-only cards could do, Seek, Perpetually, and Conjure actually seem like they fall on the tame end of the spectrum to my eyes
While some percentage of decks might want both halves of the card, it's likely an equally great percentage that will just want a wrath, and Dawn doesn't actually provide any real value (while just having Dusk with Dusk flashback would be great)
Building Soundwave, Sonic Spy as your Transformers Commander can be done, it just needs a strong focus on token Creatures, forsaking the midrange and control aspects that white, blue and black decks are well known for
Is it even a good test to do these days
You can find any of the cards from the precons in Collector Boosters (often with special treatments like surge foils, extended art, or foil-etched treatments), but you can also find cards not included in the precons , like Crucible of Worlds and Ravages of War, with borderless Vault Boy artwork: Fallout s rarest cards are the serialized S.P.E.C.I.A.L. Bobbleheads : The Vault-Tec bobblehead collectibles from Fallout are represented on cards, and each of the seven stats (Strength, Perception, etc.) has a serialized double-rainbow foil card limited to 500 copies