Jim Raynor stars as Terran protagonist. Also "Blizzard has implemented character dialogue trees into the mix. So, instead of just watching in-game cut-scenes (WC3) or non-interactive dialogue panels (SC), you can click on characters surrounding Raynor on the bridge to engage them in conversation."
"The new unlock system in StarCraft II allows players to pick and choose which units and research options they have for successive missions, instead of being fed upgrades over the course of a linear story."
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