Same goes for Wizardry series. Responsible for birthing or influencing half the games industry. (Missing branch - Influence over Portopia NES that leads to birth of Japanese ADV and VN genres). [CREDITS - Taigen Moon/The Cellar]
I think a lot about how the Ultima series helped to invent/popularize RPGs, first-person games, immersive sims,and MMORPGs, and yet basically has 0 modern relevancy.