Liked Mass Effect? Want to play its spiritual predecessor and major inspiration? Star Control II is a critically acclaimed science fiction video game from 1992 much in the same vien as Mass Effect:
DEEP and open intergalactic exploration with your actions having major effect on your environment the multi-branch story line.
Digitized voice with diplomatic speech trees and relationships with other races.
Deep plot and storyline that evolves and builds as you play.
Planetary exploration and resource gathering.
Space combat that is fun as hell.
The fact that the voices were fully digitized is absolutely insane for 1992.
The game is a fucking monument to sci-fi gaming in general.