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Immortal: Will be equipped with a shield that activates only when hit by heavy weapons like siege tanks, making them excellent for assaulting heavily defended positions but weak against raiding parties.
Colossus: True to it's name, the colossus is an enormous four-legged walker that rakes the ground with a heavy beam weapon. They will be extremely effective against small swarming units like zerglings.
Zealot: Zealots are the standard infantry unit of the portoss from starcraft.
