Earlier today, Randy Pitchford revealed a Borderlands 3 tech demo during an Unreal Engine presentation at GDC. Mr. Pitchford hinted that the game may take place in a completely new planet (all previous Borderlands titles take place on Pandora or its moon), and the footage shared during his presentation was set in a desert environment.
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Borderlands 3 is in development now, but no release date has been set so far.