Medics lack any offensive capability, but instead heal fellow infantry. Marines and firebats may make more liberal use of stimpacks when supported by medics; the increased firepower may be sustained so long as the medics have energy remaining to heal. Medics may also heal protoss and zerg biological units. Protoss players may acquire medics via the dark archon's mind control ability.
Medics use this ability to automatically heal friendly biological units in range.
1 (per 2 hit points)
Medics remove parasite, ensnare, plague, devourer's corrosive acid (removes all multipliers of acid in one cast), maelstrom, lockdown, optical flare, and irradiate, from a targeted unit; a single cast removes any combination and number of negative buffs from the above list from the target unit.
Restoration can be cast on any friendly or allied unit.
The medic was intended to be included in the original version of StarCraft; like the marine, the medic was considered a "no brainer" given the prevalence of power armored soldiers in sci-fi. However, there wasn't enough time to put it in the original game. Adding a healing unit for the terran faction made a lot of sense for the developers, as the terrans leaned more towards defensive playstyles.