Affinity goes up when you fuse your heroes(combine hero in battle that use stamina). Increase your hero affinity to get rewards such as crystals, souls and skin points that are used to buy skins.
For 1 star hero, their affinities increases when they are used as material for higher grade heroes. For 2 stars hero and higher heroes, their affinities increases when they have been summoned though fusion.
Affinity can only be earned in modes that use stamina. Affinity cannont be earned from multiplayer.
Affinity does not increase when you fail to clear stages.
