How do you pronounce the name of this series?

Kay. So I've now played through two games in this series, and I'm starting a third. I like it enough so that I'd like to call myself a fan. So I'll be going out of my way to play other games. But I feel if I'm gonna be a fan of this series, I should at least be able to pronounce the name.

So like... Ys. I get that it's the mystical land of some importance to the first few games, and Origin. But none of the games I have played (Origin, IX, or VIII) say this out loud. So help me out here.

I have been calling it "Wise." I've also been hearing it called "Ees" or "Yis." What's correct?