In MIA Online, Soul Cards can greatly enhance your attributes. Therefore, learning to upgrade the Soul Cards is essential in the game.
In the Soul Card UI, tap on a specific Soul Card then upgrade the selected Soul card. Upgrading a Soul Card requires consumption of same soul fragments before you can proceed in upgrading.
The system will give Soul Card fragments when you summon a specific Soul Card that you already own. You need a certain amount of Soul Card fragments before you can proceed to upgrading a specific Soul Card.
You can also purchase a corresponding Soul Card fragment in the Soul Card shop by spending the “Soul Card Soulstone”