Do I need the clue for the card upgrade box to spawn?

FelisCatus

I'm fairly certain I do need a clue for it to spawn much like a treasure chest or survey. If so is there anyway to get more clues? I'm getting terrible rng when it comes to clue drop rate from matches and daily win rewards.

Kappachi

Play Tales of Tribute to get more clues, it's a random drop from the rewards you get in the mail.

Katheriah

Yeah just from the mail rewards, but my RNG is horrible atm. I'm just not getting the new ones, while I got them almost instantly on PTS.