Health and Skill Cooldown
Your Hero health bar is either blue or red and is shown above their head. Keeping an eye on your health and knowing when to turn away is crucial to surviving in the intensive fight. There is green cross randomly placed on the battlefield and it can replenish your health. Often running away from the action will keep your Hero alive for longer and allow you to return to the action promptly.
Skill Cooldown works in a similar way. Every Hero has 3 skills that they can utilize. Understanding your Hero attack will help you to master the skill usage efficiency, and give you one up on your enemies.