Instead, you can add counters over time to add up to its threshold and unlock its abilities
So without comment a few more cards that interest me before I get to my top card
Volo, Street Urchin of placing Mind Over Matter Like a lot of endlessly tunable decks, the simultaneous broadness and specificity of this list asking only for some of the best creatures in Red & Blue, but also within the constraints surrounding enchantments, and otherwise limited space just keeps me coming back for more, and I would wager quite a lot of Polymorph/Scramble lists are similar
You can't choose new ones
one Shiny promo card featuring Fidough, Maschiff or Greavard
Beyond that, if you have access to a printer, thats typically your best bet for cheap proxies