Keep doing that until its XP indicator increases. When that happens you must provide it with additional duplicate cards to Lost Ark Gold "Awaken" the game (push it into the following level).
The higher the Awakening Level the more duplicate cards you'll need to take it to Level 2. The duplicate cards required by each Awakening Level are listed below.
Awakening Level 1: One duplicate cards
Level 2: Awakening. Two duplicate cards
Awakening Level 3 Three duplicate cards
Awakening Level 4: Four duplicate cards
Awakening Level 5: Five duplicate cards
Be aware that there are a lot of duplicate cards to unlock cards, it's always a sensible idea to not feed a duplicated or duplicated card to increase its XP gauge. Instead, it's more efficient to just give it XP cards.
These XP cards in the same way as Buy Lost Ark Power leveling other cards you get by completing various activities within the game. But, they also come with the rarity system, with the most rare cards giving more than XP (up at 9000).
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