If you not interested when some troops and heroes having low health, You should reach to find Fountain of Health. Unlike with other Neutral Buildings, the Fountain of Health does not need to be activated by mouse clicking. Instead, the Fountain automatically regenerates the hit points of nearby Heroes and non-mechanical units.
Regenerate 1% of the unit's total Hit Points per second.
Like Healing Ward, this is what when Witch Doctor can use Healing Ward, it takes 30 Seconds.
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Hello uses a Fountain of Health to heal the Archmage while the Creeps are sleeping.