Warcraft III style.
These are the current Terran's Champions.
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Units type (Like HotS)
Tank:
Dive right into a melee, soaking up damage and dealing it back.
Hunter:
More specialized roles that bring different strengths as you build a team.
Support:
Swing the tide of battle, assisting with healing, buffs, or other abilities to manipulate the battle in the favor of allies.
Assault:
Deal tremendous damage and can pick off unsuspecting enemies, but must choose their battles carefully, as they can dish more than they can take.