Hello o/
You would need to get at least 400 packs, considering getting the card that you want in every pack (but that is random). That number is because to get a card to max level, which is 10, you need to combine 400 copies of it.
What league are you playing at?
- At bronze, for example, the max level of monster is lvl 3, which is 14 cards combined. If you have a higher level card it'll be caped at 3.
Hope it helped 😀👍
I'm in Novice League
At the novice league the max level is 1bcx, here is where you can find it:
So, you'll only need one copy of the card.