Game Usage
 Terran vs Zerg
Medics, along with Marines, are the most common unit in Terran vs Zerg. Their healing ability makes Marines very cost efficient. Medic walling is a micro technique that is used to prevent melee units from attacking the Terran's ranged units, such as Marines and Siege Tanks.
 Terran vs Protoss
Since Terran vs Protoss usually consists entirely of Factory units, Medics have no use. However, they can still be helpful if the Terran opts for an early Marine/Medic timing attack.
 Terran vs Terran
Since Marines are rarely used past the early game, Medics are useless against other Terrans.
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