Level Up

Leveling up a card increases attack and health by 15% of the card's base values. The cost of leveling up depends on rarity and current level. All cards start at level 1.

Gold cost
Gold cost increases by 15% for each level (exponential). The cost is proportional to rarity of the card: GoldCost = Rarity * 2300 * 1.15 ^ (Level - 1)
 * Common: 1x
 * Rare: 2x
 * Epic: 3x
 * Legendary: 4x
 * Mythic: 5x

for leveling up to Level.

Normal Cards
Leveling up a card also costs a certain amount of items. Items come in tiers ranging from one star to five stars.
 * Elixir (depending on elemtent, e.g. Earth Elixir for earth cards)
 * Necklace (depending on rarity, e.g. Common Necklace for common cards)
 * Misc (e.g. Wisdom Book or Precious Ring)