I think "Requiem" sounds very close to modern day trap, it would have been revolutionary back in 1996, haha! It's nice.
Mmm, beautiful, Castle Iris is good. About the theme: "haunting relentless ticking motif"? Nonono, what truly fits the theme here is the fact that if this was playing in the background, while being chased by a crazy dude I would have sh@t my pants. It's the sense of urgency and partially fear that makes it fitting. I like it. I think that without the piano it would have been even better. But that's personal preference.
Rattrapan had my head bobbing, his theme is fire. Maybe it doesn't fit the game genre perfectly but it's pretty fun.
Eternity Engine is well engineered in terms of sound design.