Throughout the game, you will get the opportunity to upgrade your Spells and Heroes.
Spells can be upgraded by collecting Spell Cards from Spellbooks and from Quests. Once a Spell has enough Cards as indicated on the Spell icon in each Heroes’ Spells menu, it can be upgraded to the next level for the amount of Gold indicated.
Heroes gain experience points (XP) for each if their Spells that are upgraded. Once the Wizard has gained enough XP, as indicated in the Spells menu, they are automatically upgraded to the next level, increasing their health.