SCLegacy had an awesome lore interview with Chris Metzen discussing Terran and Protoss history in previous Starcraft games and what they mean for the storyline of Starcraft II. Topics touched in the interview are:

Duran
Protoss Executor Selendis
Cerebrate Daggoth’s fate
Return of the Cerberus Terran Unit
Adun’s story on the Starcraft Novel
Kalath Intercesion lore explained
Why the Uraj crystal ended [...]

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