Below is a list of the cards you can purchase multiple times at the Stormbound: Kingdom Wars shop along with their cost.
New Common Card
Cost: 200 Coins
Can be purchased 5x per day
+40 Coins for each step
Owned Common Card
Cost: 80 Coins
Can be purchased 5x per day
+40 coins for each step
New Rare Card
Cost 500 Coins
Can be purchased 3x per day
+100 coins for each step
Owned Rare Card
Cost 200 Coins
Can be purchased 3x per day
+100 coins for each step
New Epic Card
Cost 80 Rubies
Can be purchased 1x per day
Owned Epic Card
Cost: 40 Rubies
Can be purchased 1x per day