Heroes are your special character card.
After login the first time you will need to create a Hero. The Hero you create in Dragon Evo - Twisted kingdom will decide your cards strengths and weaknesses & what faction card you can have in your deck.
Your Hero´s faction decides which Champion cards you can have. You will only be able to use creature cards from your own faction. Too see available champions and units, see the cards section.
You will be able to buy additional heroes for ingame currency Adaptorite which can be gained by playing the game.