Velrun, I know how it works. I'm doing it for all my custom cards, though I like to use a placeholder that's close in function and casting cost. Like I already argued though, not all problems solved. As soon as Arcane Signet is released for real on CT, I'ld have to replace the Arcane Sanctum with the real deal, and all decks featuring the fake Arcane Signet will now contain an Arcane Sanctum instead. Unless I sideboard the proxy, but that'll pollute my sideboard fast. All of the metrics CT gathered will also be gone. I'm not saying it can't be done, I'm saying it's not as perfect a solution as releasing the cards within 24 hours of them being spoiled. If I could choose, I would much prefer CubeCobra's solution over fiddling with custom scans, and it's not particularly close. I get that it's not a sticking point for you, but it is for me, which is why I wait for the official release on CT before adding cards from a new set nowadays. Like I said, let's agree to disagree.