As part of the June 26 (PT) update, we will be adding a feature to trade for temporary cards using temporary gems.
Temporary gems are a new item that can be earned by playing matches.
Temporary cards can be used to build decks and play matches just like any other card, but they cannot be liquefied or animated with seer's globes. They will show up in your card collection like any other card but are noted with an orange number.
Temporary cards are special cards available in your collection for a set period of time. Details on how long temporary cards are available for will be revealed in a future announcement.