Don't forget that the TARDIS itself is a separate card
Protect your people, punish your enemies, and preserve your position as commander and king
Creature - Eldrazi Color tag templates(None) Finisher (CTRL to add secondary) Scion of the Ur-Dragon Flying : Search your library for a Dragon permanent card and put it into your graveyard
One is to check the singles listing for each expansion on Star City Games and sort by descending price, but you'll need to filter out foils, and SCG has fixed prices for low-circulation cards
Wizards confirmed that youre protected from opening duplicates, with a couple of caveats: If you open a rare or mythic rare Mystical Archive card that you already own a playset of, itll be replaced with another Mystical Archive card of the same rarity
Sliver Legion would be my personal favorite to copy a bunch and could represent a ton of damage