Ethereal cards

[Brainy]

so i came back and finally beat the 2nd location boss, it gave me the ether potion and i just noticed you cant do anything with that thing unless im blind, doas that mean you have to unlock ALL golden cards in a deck before you can even do a ethereal upgrade to a golden card or what? if yes thats a pretty bad mechanic tbh, why not give us the oportunity if we beat the 2nd boss to at least give a alrdy unlocked golden card the ethereal upgrade? ......

[fluxtorrent]

you need all the cards in a set to be gold first, then you need 1 potion, it resets everything else to be grey and you need to build the rest up to gold again. Then you need 2 potions for the second and so on and so forth.

[The Nothing Man]

ty for this, that is insane to get to just that deck set, as I dont even have deck 1 solid gold
ffs
this game !