Your heroes’ stats can increase both through earned XP and level-ups, and through increasing the hero’s rarity.

A hero levels up by earning XP in battles — as long as they took part in them. You can also upgrade a hero’s level with Gold: the higher the level, the more expensive the upgrade.

A hero’s level cap depends on the Barracks level: a hero can gain 10 levels for each building level. For example, you can upgrade them to level 10 with Barracks level 1, to level 20 with level 2, and so on. If a hero reaches the cap, they won’t gain XP until you upgrade the building.

Hero rarity is upgraded using their named coins, which you can earn by clearing floors of the Tower of Trials.