To evolve your heroes you need to get more medals. There are different ways to get medals:
- Open a free or premium chests, if you already have the hero, those will reward the equivalent amount of medals for that hero.
- Play at the daily dungeon, each dungeon will reward a medal from its element. Ex the Dark Knight dungeon will reward a random medal dark hero medal.
- Go to the guild shop and use your guild coins to buy medals from 3 different heroes. The shop content will change every 24hours.