Zhao wrote:You need certain amount of gems to crafting cards, then when you craft then, the previous cards will be gone.
Example : you need 400 yellow, 200 green gems and 2 white cards to craft a green card.
You will need to make another 2 white cards and having enough gems to craft another green card.
same goes with blue and purple card.
8 white cards would make 4 green. 4 green makes 2 blue. Then 2 blue would be a purple card.