Merics have a medium amount of health and can heal themselves,but they have almost unnoticeable damage so they can't defend themselves.
The Meric has one ability that must be researched,while the other is always with the monk on training completion.
Heal:Heal allows the meric to heal a portain of a single unit's health one at a time. It is a default ability with no need to train.
Cure: Cure allows the meric to instalty cure posion on a single unit at a time.