This game started my love for JRPGs and to this day remains the most unique game setting I've seen. The atmosphere of this first one, especially, is so dark and edgy. It almost feels like the show supernatural. This game doesn't try to make every scene a joke and that really helps the mature tone of the game. The story is pretty epic and the characters are fantastic all around.
Alot of people prefer the 2nd game and Covenant is indeed amazing. But I still think I like this first one better. Alot of that "dark" vibe that makes Shadow Hearts so great goes away in the 2nd entry and by the 3rd it's completely gone.